Potted Mandevilla: Home Care and Management Tips
Mandevilla is a new type of climbing plant, also known as red wrinkled vine, double gland vine, double happiness vine, wen vine, and red cicada flower. It is native to tropical America and is a perennial evergreen plant of the Apocynaceae family. The twining stems of Mandevilla are soft yet tough, spiraling upward along a support, and its pink trumpet-like flowers are large and upright
Mandevilla is a new type of climbing plant, also known as red wrinkled vine, double gland vine, double happiness vine, wen vine, and red cicada flower. It is native to tropical America and is a perennial evergreen plant of the Apocynaceae family. The twining stems of Mandevilla are soft yet tough, spiraling upward along a support, and its pink trumpet-like flowers are large and upright, with flower stems reaching 6-8 cm. During the blooming period, Mandevilla often displays a spectacular show of more flowers than leaves. When a breeze blows, waves of refreshing fragrance fill the air and delight the heart. This is how it earned the elegant name "Mandevilla" (fragrance-drift vine). Below, the editor explains the care and management techniques for Mandevilla.
Light and Temperature
The "Samba Dance" series prefers a warm environment with ample sunlight and is not cold-tolerant. The optimal growing temperature is 20°C-30°C, and growth is inhibited when outdoor temperatures fall below 7.5°C. In the Beijing area, it must be kept indoors to overwinter against the cold. It may lose its leaves during overwintering and will not bloom again until spring.
Growing Medium
The "Samba Dance" series has strong adaptability to soil. For the potting mix, it is best to choose a well-draining medium with added amendments and humus.
Watering
Soil that is too dry affects fertilizer absorption, while soil that is too wet causes root death or other diseases. Especially in winter, watering should be reduced to keep the soil dry. In summer, increase watering and avoid letting the soil dry out completely.
Fertilizing
The "Samba Dance" series requires proper fertilizing during the vigorous growing periods of spring and summer. Apply a balanced slow-release fertilizer to the potting soil, then apply a liquid fertilizer once every 7-10 days. If leaf tips show signs of scorching, or black spots appear on the top and sides of the leaves, it indicates the plant may be lacking nutrients.
Pruning
Mandevilla is generally pruned at two times: after the blooming period and in spring. Pruning after the blooming period can shape the Mandevilla to make it more attractive. Pruning old plants in spring can promote the sprouting of new branches.
Pest and Disease Control
Diseases are mainly leaf diseases such as leaf spot and leaf blight caused by Cercospora, as well as root rot and stem rot caused by Fusarium. In the early stages of disease, fungicides such as carbendazim and mancozeb can be used for control. Spider mites and whiteflies are the most damaging insect pests and can be controlled with imidacloprid and similar products.
Repotting
The "Samba Dance" series grows very vigorously and easily fills the pot, causing nutrient deficiency, which results in yellowing of the lower leaves and failure to bloom. Therefore, it should be repotted into a larger pot in a timely manner. When repotting, remove the old support and wind the trailing branches around a new support.
The above are the care tips for Mandevilla introduced by the editor. Mandevilla needs plenty of sunlight during cultivation; insufficient light will lead to reduced blooming.
Is Mandevilla Toxic? How to Grow Mandevilla
Below, the Flower and Bonsai Network introduces knowledge on how to grow Mandevilla. It will also cover whether Mandevilla is toxic, the value of Mandevilla, and other information.
Mandevilla (scientific name: Dipladenia sanderi) is a new type of climbing plant, also known as red wrinkled vine, double gland vine, double happiness vine, wen vine, and red cicada flower. It is native to tropical America and is a perennial evergreen plant of the Apocynaceae family. The twining stems of Mandevilla are soft yet tough, spiraling upward along a support, and its pink trumpet-like flowers are large and upright, with flower stems reaching 6-8 cm.
Mandevilla prefers a warm, humid environment, but its branching habit is poor. During the blooming period, Mandevilla often displays a spectacular show of more flowers than leaves. When a breeze blows, waves of refreshing fragrance fill the air and delight the heart, which is how it earned the elegant name "Mandevilla."
Mandevilla belongs to the Apocynaceae family, and many people know that plants in the Apocynaceae family are toxic. So, is Mandevilla toxic? Where can it be kept?
Is Mandevilla Toxic?
Many plants in the Apocynaceae family are toxic, but whether Mandevilla itself is toxic has not yet been clearly determined. Mandevilla has a rich fragrance, and some people worry about whether this scent could cause poisoning. However, so far there have been no cases of poisoning from growing Mandevilla. Everyone loves the fragrance, and few people experience discomfort from it, so although Mandevilla's fragrance is strong, it can still be grown with peace of mind.
Where Is Mandevilla Suitable for Growing?
Mandevilla can be grown both indoors and outdoors. When grown indoors, it can be made into a potted plant, placed on a balcony or similar spot, or grown as a hanging plant. When grown outdoors, Mandevilla can be used on fences, trellises, or as a small courtyard landscaping plant. When cultivating outdoors, be careful not to plant it in low-lying areas to avoid soil waterlogging that could cause poor plant growth.
Precautions for Growing Mandevilla
When growing Mandevilla indoors, be sure to provide sufficient light. If light is insufficient or the growing environment is too shaded, it will lead to reduced blooming.
Growing Mandevilla indoors can purify the air, and its beautiful flowers also emit a rich fragrance, making the indoor environment purer.
In addition, when growing Mandevilla, as long as you pay extra attention, you can reduce the possibility of poisoning. You never know, Mandevilla may also have unexpected benefits!
Mandevilla Growing Methods and Precautions
Mandevilla is also known as red wrinkled vine, double gland vine, double happiness vine, wen vine, and red cicada flower. It is named "fragrance-drift" because Mandevilla releases waves of delightful fragrance when it blooms. So, what exactly are the growing methods for Mandevilla, and what precautions should be taken?
Growing Methods for Mandevilla
Light Requirements: Mandevilla prefers a warm, humid environment with ample sunlight. Sufficient light is needed to ensure normal growth of Mandevilla; partial sun to full sun is acceptable. Of course, Mandevilla can also be kept in a slightly shaded location.
Water and Fertilizer Management: During the care of Mandevilla, water and fertilizer management should be done well. Regarding watering, control the amount; do not let it become waterlogged or too dry, which would cause poor plant growth. Good water and fertilizer management will help develop a strong root system, and only then will Mandevilla grow vigorously. During the growing period, apply a compound fertilizer 3-5 times as a top dressing.
Temperature Requirements: The optimal temperature for Mandevilla growth is between 20-30°C, and it is best not to exceed 35°C. In winter, when temperatures are too low, it is prone to frost damage, so attention should be paid to maintaining warmth in winter, preferably not below 10°C.
Soil Selection: Mandevilla has low soil requirements and strong adaptability, but a sandy loam rich in humus with good drainage is best.
Propagation Methods: Mandevilla is generally propagated by cuttings, and tissue culture can also be used for rapid propagation.
Pruning: Mandevilla is generally pruned at two times: after the blooming period and in spring. Pruning after the blooming period can shape the Mandevilla to make it more attractive. Pruning old plants in spring can promote the sprouting of new branches.
Precautions for Growing Mandevilla
Light must be sufficient; insufficient light will lead to reduced blooming of Mandevilla.
When fertilizing, control the amount of nitrogen fertilizer applied to prevent the Mandevilla plant from growing too vigorously due to excessive nutrients, which would affect blooming and reduce flower production.
Although Mandevilla has strong stress resistance and is rarely affected by diseases, preventive measures should still be taken.
When Does Mandevilla Bloom?
Mandevilla is grown primarily for its flowers. Once the beautiful flowers open, they are enough to catch everyone's eye. Are you eager to know about Mandevilla's flowers? Let's take a look at when Mandevilla blooms.
The Blooming Period of Mandevilla
Mandevilla's blooming period is actually quite long, mainly concentrated in summer and autumn. Mandevilla blooms from April to October, lasting nearly half a year. It can be said to be very long-lasting.
Mandevilla's Flower Shape and Color
Mandevilla's flowers are somewhat trumpet-shaped in appearance. The flowers are very large and upright when open, with flower stems reaching 6-8 cm. Mandevilla's flowers are mainly axillary, with a funnel-shaped corolla and 5 petals. The petals overlap in layers, arranged in a pleasing, well-proportioned way, and the flower shape is very elegant.
The colors of Mandevilla flowers are mainly in the red range: red, peach red, golden red, pink, and other colors, rich in variation, and sometimes there are other colors as well. They look colorful and delightful to the eye.
The Flower Language of Mandevilla
The flower language of Mandevilla is love and virtue. Such beautiful flowers, full of rich fragrance, are just like love and virtue: both beautiful and unforgettable.
Precautions for Mandevilla Blooming
Mandevilla's blooming period is mainly in summer and autumn, but with proper care it can also bloom in other seasons.
After a long blooming period, Mandevilla has entered autumn. Blooming consumed a large amount of nutrients, and after the flowers faded, a large number of old branches, dead branches, and spent flowers remained. Therefore, pruning can be done after the blooming period. Pruning at this time is mainly for shaping, to make the entire Mandevilla plant look more attractive.
Reduced blooming may be due to insufficient light or excessive fertilizing. In daily care, pay attention to increasing light exposure and fertilizing reasonably to avoid excessive nutrients and overgrowth of the plant.
The Value of Mandevilla
Mandevilla has large, brightly colored flowers and a beautiful plant form, and is known as the queen of tropical climbing plants. Is such a beautiful plant only for ornamental purposes, or does Mandevilla have other uses?
The Ornamental Value of Mandevilla
Being ornamental is an important function of Mandevilla. Its flowers are beautiful and often bloom profusely, displaying a spectacular show of more flowers than leaves. Mandevilla has high ornamental value.
Mandevilla can be cultivated outdoors. When grown outdoors, it can be used on hedges and fences, trellises, rooftops, and for small courtyard beautification. It can beautify the environment and provide ornamental enjoyment, adding a touch of brilliance and freshness. However, when cultivating outdoors, pay attention to the planting site; do not choose low-lying areas to avoid waterlogging.
Mandevilla can also be grown as an indoor potted plant. Mandevilla actually does not have a strong trailing habit and is quite suitable as a small potted plant, placed on balconies, windowsills, corridors, steps, and other places to decorate the home. Mandevilla can also be shaped into a ball or hung as a hanging basket, which is very unique and can give the home an exotic atmosphere.
When placed indoors, Mandevilla not only beautifies the indoor environment but also fills the room with fragrance.
The Air-Purifying Value of Mandevilla
Mandevilla can purify the air, which is also very important. Placing Mandevilla indoors can absorb harmful substances such as benzene and formaldehyde from the air, as well as some dust, making the indoor environment purer. Outdoors, Mandevilla has a certain absorption effect on sulfur dioxide and other toxic components in the air, with a relatively obvious effect on purifying the environment.
Other Values of Mandevilla
Mandevilla can be used to extract essential oil. When Mandevilla blooms, its fragrance spreads everywhere and is very rich. Its flowers contain a large amount of natural volatile oil, from which natural essential oil can be extracted. The essential oil from the flowers has many benefits for people. It can refresh the mind and regulate emotions.
How to Care for Rixianggui (Fragrant Osmanthus)
Rixianggui is a horticultural variety of osmanthus, named for its characteristic of continuous blooming and rich fragrance. Rixianggui's fragrance spreads in all directions and is refreshing to the heart. Its most notable advantage is that flower stems extend beyond the green leaves, and it can bloom year-round with continuous flowers. Below is an introduction to the cultivation and daily care techniques for Rixianggui.Cultivation of Rixianggui:
1. Substrate Selection: Use loose sandy loam containing organic matter. Mushroom residue, sawdust, peat, and mountain forest leaf mold can also be used (the substrate should be chosen so that the potted plant's root system can grow and breathe). The pH of the substrate should be neutral, slightly on the acidic side. After choosing the substrate, it is best to also carry out disinfection and sterilization treatment (such as using thiophanate, dijunqing, carbofuran, and other agents).
2. Watering: Newly planted specimens should be watered thoroughly once. After that, follow the principle of "water when dry, stop when wet." Too much water will cause root rot. However, avoid watering with alkaline water such as tea water or laundry detergent water.
3. Fertilizing: Because Rixianggui consumes more nutrients due to its continuous blooming, more phosphorus fertilizer should be applied to promote continuous flowering. Based on this, Rixianggui's fertilizing standard should follow the principle of "light fertilizer, frequent application." Organic fertilizer can also be added in moderation normally, but never fertilize excessively or too frequently. Fertilizing should be combined with watering, generally once per blooming period.
4. Pruning and Shaping: According to the desired tree form, cut off some leggy branches, overly dense branches, dead branches, and diseased branches. For newly planted potted plants, a portion of the tender branches should be pruned. Pruning is generally carried out after the tender shoots sprout but before they have become woody.
5. Pest and Disease Control: Common diseases of Rixianggui include leaf blight and anthracnose, which can be controlled with 800x dilutions of "Duojunqing" and "Thiophanate." Common pests include spider mites and scale insects, which can be controlled with 1000x dilutions of "Chlorspider-mite-kill" and "Supujie" respectively.
Daily Care of Rixianggui:
1. Light Management: Newly planted Rixianggui should be shaded. Shading is also needed in summer, with a shading rate of about 80%. To promote continuous blooming of Rixianggui, light should be appropriately increased in winter.
2. Temperature Control: The normal blooming temperature for Rixianggui is 2°C to 22°C. If summer temperatures are too high, the temperature can be reduced and humidity increased by misting the leaves. If winter temperatures are too low, insulation measures should be taken.
3. Humidity Control: Normal humidity can be maintained at 70% to 85%.
4. Repotting and Soil Changing: Rixianggui that has been potted for too long or has grown too large should be repotted and have its soil changed in a timely manner. This can both increase soil fertility and keep the root zone soil loose and breathable, ensuring the vigorous growth of Rixianggui. Repotting and soil changing can be determined by its growth condition, generally once every one to two years.
5. Promoting Blooming: The optimal temperature for flower bud differentiation of Rixianggui is 6°C to 8°C. The temperature for maximum blooming is 16°C to 18°C, with air humidity of 75% to 85%. At the same time, a certain amount of short-day light is needed. Therefore, we can promote its blooming by improving the micro-environment (such as removing buds to control vegetative growth, shading to control light, misting leaves to reduce temperature and increase air humidity, etc.).
Rixianggui Potted Plant Production and Care Techniques
Rixianggui is a rare treasure among osmanthus and is a new osmanthus variety bred in recent years. It is deeply loved by people for its beautiful tree form, year-round deep green foliage, pleasant fragrance, and its symbolism of wealth (gui) and peace. A two-leaf seedling of the current year can bloom, which is unmatched by ordinary osmanthus. Even in the coldest months of winter, it can bloom all over the tree with fragrance filling the air, which can be called extraordinary. It is an excellent gift treasure -- place two pots in the courtyard to fully display elegance. So, for this precious tree species, how should home potting be cared for so that it grows well?
Rixianggui is a treasure among osmanthus, named for its characteristic of continuous blooming and rich fragrance. It has many branches and short internodes, with a full and compact tree form, smooth leaves, and year-round emerald green foliage. It blooms extremely early, and the most extraordinary thing is that a two-leaf seedling from a current-year cutting can bloom. Its blooming period is extremely long, with a fragrance similar to the strong-fragrance type of golden osmanthus. When potted in the north, Rixianggui has a rich fragrance that fills the air, making your living environment fresh and beautiful and keeping you in good spirits.
I. Planting. The best planting time for potted Rixianggui: spring is March-April, and autumn is August-September. For the potting soil, it is best to choose loose, fertile, well-draining sandy loam, while adding 0.2% ferrous sulfate. Place some breathable material at the bottom of the pot, then fill the pot with growing medium and water thoroughly. After planting, cover with plastic film to maintain humidity in the pot space, and place in a shaded area for care. After new leaves emerge, remove the cover and move to a sunny location.
II. Fertilizing. Newly planted Rixianggui seedlings must not be given top dressing. After the seedlings sprout branches and unfold leaves, spray with a 0.1% potassium dihydrogen phosphate solution once every 7-10 days. The fertilizing principle is light fertilizer, frequent application. In spring and autumn, apply a dilute decomposed soybean cake fertilizer once every 10-15 days. In summer and winter, apply no fertilizer or very little. During the growing period, an appropriate plant nutrient solution can be sprayed as needed.
III. Watering. Rixianggui prefers moisture, fears waterlogging, and is not drought-tolerant. During plant growth, watering follows the principle of "water when dry, stop when wet." Water as soon as the surface of the potting soil dries, always keeping the potting soil moist. Especially in summer and autumn when temperatures are high and the air is dry, in addition to watering more, frequently mist the plant surface to prevent leaf edges from scorching dry. Water accumulation in the pot will cause root damage and root rot, so attention should be paid to this.
IV. Pruning. Letting it grow freely is a major taboo for potted Rixianggui. Rixianggui has strong sprouting ability and tolerates pruning. Removing the top of upright main branches can encourage more new branches at the base, expand the canopy, and strengthen the main branches. For clustered upright main branches, the tree form can be opened up by bending and pulling the branches.
In addition, potted Rixianggui also requires attention to winter insulation and cold protection, and in midsummer, prevention of high temperatures and scorching sun burning tender leaves and young buds. Pay attention to removing buds from seedlings, timely control of pests such as spider mites and scale insects, and timely repotting and soil changing.
First, Rixianggui prefers light. In winter, if you want Rixianggui to have a rich fragrance, it should be placed in a warm, sunny spot {the best is to place it on a balcony if the home has one}. Indoor placement should also be in a position where sunlight can reach it. This is because the heat from sunlight is enough to release the fragrance. Otherwise, in a dark, damp, and cold place, even if Rixianggui is full of flowers, the fragrance will not be strong enough.
Second, Rixianggui prefers moisture, but in winter, because the weather is cold and water evaporates slowly, potted Rixianggui needs less watering. Generally, watering once every 5-10 days is appropriate {determined by the dryness of the surface soil}. Watering too frequently can easily cause waterlogging damage. In summer, because temperatures are high, large pots of osmanthus should be watered every 2-3 days (water thoroughly when watering). Management in spring and autumn is much easier, as these are the peak growing seasons and also the peak blooming seasons. You can adjust as needed and prune and shape according to your own preferences.
Third, Rixianggui prefers fertilizer and can be regularly given compound fertilizer. Apply light fertilizer frequently, not concentrated fertilizer. Depending on its growth condition, it should be repotted once every 1-2 years. The soil should preferably be loose soil with good water permeability. With proper care, it will certainly have luxuriant branches and leaves and delightful growth.
In summary, Rixianggui has good adaptability, is easy to plant and keep alive, requires minimal management, has very few pests and diseases, and combines green, beauty, fragrance, and uniqueness in one. It is an ideal tree species for home greening and beautification. Place two pots in the courtyard to fully display elegance!
Greenhouse Potted Cultivation Guide for Rixianggui
Osmanthus is native to our country and is one of China's traditional famous flowers. Its uniquely representative fragrance has long been known and loved by people. Rixianggui is a new variety of four-season osmanthus, belonging to the Oleaceae family, with flat, broad leaves without serrations. It blooms from a young tree; young trees bloom for more than 260 days a year, and mature trees bloom continuously throughout the year. The flowers are large and the fragrance is rich, earning it the reputation of "rare flower with extraordinary fragrance." It is currently the only recognized osmanthus treasure that blooms fragrant flowers year-round.
Rixianggui has many branches and dense leaves, is evergreen year-round, and has a well-proportioned, full tree form. It is both a rising star among landscaping trees and a new favorite among potted flowers for the New Year, and is gaining favor with more and more consumers. In order to introduce and promote this variety and meet market demand, some enterprises have begun to attempt large-scale production. However, compared with field planting, potted Rixianggui's root system activity range is easily affected. To ensure the plant has abundant branches, many flowers, and a rich fragrance, cultivation management needs to be strengthened. Based on production practice, the author conducted preliminary research on the large-scale production technology of potted Rixianggui, and now summarizes the key points of its propagation and potting techniques as follows.
Propagation
Because osmanthus has few seeds and they are difficult to obtain, and grafting is also not ideal, cutting propagation is mostly used. Among these, softwood cutting propagation has the advantages of easy material collection, simple operation, and a high survival rate.
The author introduced 1000 mother plants of Rixianggui from Sichuan. After several years of careful cultivation of the mother trees, in May-June, strong semi-lignified softwood shoots of the current year were cut as cuttings. Then in August-October, semi-mature branches were cut again. Cut branches should be kept moist, placed in sealed plastic bags or buckets as much as possible, and protected from strong light. Cutting material is generally cut into short cuttings with two leaves and one short stem. Cutting and trimming should preferably be done in the morning. The cutting bed needs to have the soil tilled and prepared in advance, and shade should be set up. When inserting cuttings, keep them neat. The insertion depth should be enough to cover the leaf petioles. The cutting density should be appropriately sparse: with a plant spacing of 3-5 cm, about 300,000 cuttings can be inserted per 667 sq m. After insertion, spray-irrigate the seedlings with an aqueous solution of fungicide and rooting agent in appropriate proportions. After the solution spray-irrigation is completed, promptly cover with plastic film.
In the days after insertion, water timely according to soil moisture conditions to prevent water deficiency. When no water droplets are found on the inner wall of the film, or when there are few droplets, water promptly. Generally, rooting begins about 1 month after cutting, and they can be moved out of the nursery for transplanting in about 3 months. For Rixianggui cuttings inserted in autumn in September-October, because the ground temperature is not high, some cuttings do not develop roots. Seedling lifting and planting should be arranged in April-June of the following year based on the actual condition of the plant root system.
Potting and Planting
Choosing Containers
Rixianggui grows relatively fast and has larger leaves, so the pot should not be too small or too shallow, to ensure normal plant growth and blooming. Plastic pots or container gallon pots can be chosen. When cultivating, attention should be paid to a coordinated ratio between pot diameter and plant canopy diameter. Generally, for one-year-old seedlings, choose pots with a diameter of 15-20 cm; for two-year-old seedlings, choose pots of 20-25 cm; for three-year-old seedlings, choose pots of 30 cm. Never use a large pot for a small plant, otherwise the potting soil will remain wet and easily cause root rot.
Preparing Nutrient Soil
Rixianggui prefers loose, fertile, slightly acidic substrate rich in organic matter. For alkaline soil in the north, more humic acid should be mixed in, or 0.2% ferrous sulfate should be used to improve the soil. For acidic soil, plant ash, lime, and the like can be used to neutralize it. General nutrient soil is prepared in proportions using leaf mold, river sand, garden soil, and the like. Soilless cultivation can also be carried out using mushroom cultivation residue, sawdust, peat, and the like.
Potting at the Right Time
Two-leaf seedlings from cuttings have a more developed root system after planting and are also more conducive to seedling survival. Therefore, Rixianggui can be potted and planted throughout the year. However, spring and autumn are the most suitable periods for potting. When transplanting seedlings, be careful not to damage the root system. When potting, first place a piece of plastic window screen over the drainage hole at the bottom of the pot to prevent earthworms and other pests from getting into the pot. Cover the plastic window screen with 2-3 pieces of broken tile, convex side up, to facilitate ventilation and drainage. When transplanting seedlings in, the root crown should be level with the soil surface, with roots spread out in the growing medium. After straightening, fill with nutrient soil to about 3 cm from the pot rim. After firming, water thoroughly and place in a cool place to recover.
Cultivation Management
Growing Environment
Container-grown Rixianggui should be placed in a greenhouse site that is ventilated, sunny, and well-draining.
Placement Method
The placement method should facilitate management and viewing. During large-scale production, attention should be paid to placement density. Too sparse wastes space, while too dense easily causes pests and diseases. Generally, placement density is determined by plant size, with branches not crossing each other and ventilation and light penetration being favorable.
Temperature and Humidity
The micro-environment for Rixianggui growth requires a warm, humid, well-ventilated, and fresh-air environment.
Temperature: It can survive within the range of -15 to 40°C. Its normal growth temperature range is 5-32°C. The optimal temperature for flower bud differentiation is 5-12°C at night and 16-18°C during the day.
Humidity: Potted Rixianggui requires the greenhouse air relative humidity to be around 80%.
Water and Fertilizer Management
Watering: Watering is a very important task in the management of potted Rixianggui. Osmanthus prefers high temperatures and dryness, and the substrate should not be too wet, let alone waterlogged. Watering should follow the principle of "two less, one more," namely less watering before new shoots sprout, less watering on rainy days, and normally watering to maintain about 50% water content in the potting soil. In summer under high temperature and dry conditions, watering should be sufficient: water once in the early morning, and in the evening, depending on the dryness of the potting soil, water lightly again if dry. At noon, use shade netting to reduce the impact of high temperatures. At the same time, frequently spray water on the leaves and around the pot to lower the temperature, creating a good environment suitable for the growth and development of potted Rixianggui. On rainy summer days, drain promptly to prevent water accumulation in the pot from causing root rot, otherwise it may "drown."
Fertilizing: Rixianggui prefers fertilizer. After half a year of potting, fertilizer can be applied at any time. It is better to apply less than too much, and better to apply dilute than concentrated. Osmanthus is extremely sensitive to concentrated fertilizer, especially nitrogen fertilizer, and is even more afraid of inadequately fermented "raw fertilizer." Applying diluted organic cake fertilizer solution provides comprehensive nutrients and is stable and safe in nature, and can be used for various potted flowers. For chemical fertilizer, compound fertilizer is better, but attention should be paid to choosing sulfur-based compound fertilizer; "chlorine-based" fertilizer cannot be used. Generally, during the growing period, solid compound fertilizer can be scattered on the pot surface. If once every 10 days or so, a mixed liquid fertilizer of decomposed liquid fertilizer water and 0.1% potassium dihydrogen phosphate is used to irrigate once, it is very effective for strengthening newly sprouted shoots and is beneficial for the success of future flower bud differentiation. During the blooming period and the cold winter period, fertilizing can be suspended. In addition, spray a foliar fertilizer of 0.2% potassium dihydrogen phosphate and silicon-boron-manganese fertilizer once every half month to increase the growth thickness of new shoots, improve leaf function, and make the Rixianggui plant's branches and leaves look more attractive.
Light and Shade
Rixianggui (Osmanthus fragrans 'Rixianggui') is a shade-tolerant tree species that loves light, but newly planted seedlings are most easily scorched on their leaves when exposed to high temperatures and direct scorching sun for too long. In mild cases, some leaves turn white or yellow; in severe cases, the tissue necroses into a dark brown scorched appearance; and in the worst cases, the leaves wither and drop off. Once a seedling's leaves have all fallen, it is difficult for new buds and new shoots to grow. Therefore, when planting Rixianggui seedlings from May to September, they must be in an environment with shade conditions. When the average annual temperature rises to 22°C, start shading, until the end of September. Generally, the shading level of the cultivation site is 50%-60%, and black shade netting gives the best effect and is also convenient. Rixianggui has a certain cold resistance, but during the seedling stage it cannot tolerate a low temperature of -10°C. Therefore, in northern regions, when the temperature drops to severe cold, the cultivation site should promptly have a plastic film greenhouse built, and cold and freeze protection measures should be well done to avoid frost damage to the branches and tips.
Bud Thinning for Seedlings
For two-leaf seedlings from cuttings, after they have become established, the excess axillary buds growing from the two leaf axils should be removed early; otherwise, the consumption of a large amount of nutrients will affect the growth of the main branch. For newly planted two-leaf seedlings, if after establishment every axillary bud is a flower bud, it is not a problem either, but in order to save nutrients, when thinning flowers, do not remove all the flower buds from the base, because although the buds grown from seedlings planted in the low-temperature season are flower branches, small and weak leaf buds can still grow again from the leaf axils where the flower branches have degenerated. Therefore, when thinning flower buds, the leaf nodes should be retained; after thinning, the buds that emerge are somewhat stronger. In addition, during the seedling stage, leaf buds often produce flower buds, but in order to promote early shaping, all hidden flower buds should be thinned out, which is beneficial for the rapid growth of new shoots.
Potted Care of Rixianggui in the North
Rixianggui is a new variety in the osmanthus family with the longest flowering period, the most fragrant flowers, and a growth rate five times that of ordinary osmanthus. It is cold-resistant and drought-resistant, and can be grown in pots in northern regions.
I. Propagation: Outdoor cuttings are generally best taken from May to September each year, and the optimum temperature for rooting of the cuttings is 25-28°C. The cuttings generally root in 20-30 days. The potting soil is best a loose, fertile, well-drained, slightly acidic sandy loam; heavy, sticky and alkaline soils are taboo, and a pH value of 5.5-6 is suitable. Generally, mix 4 parts rotted leaves, 2 parts decomposed barnyard manure and crushed bone, and 4 parts garden soil, and appropriately mix in a small amount of superphosphate, diammonium phosphate, etc., to increase soil fertility. The best planting times are February to April in spring and September to November in autumn. Place in a shady spot to recover.
II. Watering and Fertilizing: Rixianggui likes warmth and moisture. In summer and autumn, when the temperature is high and the air is dry, water more to keep the potting soil moist. In winter and spring, watering should be appropriately reduced. In a place with sufficient sunlight, its leaves are emerald green, the branches are thick and strong, and the flowers are abundant and fragrant. In summer it fears high temperatures and scorching sun burning tender leaves and young buds; in midsummer, potted seedlings should be placed in a well-ventilated shady spot, with a shading level of about 80%.
After the new branches and tips of Rixianggui tend to become woody, mainly use phosphorus and potassium fertilizers, and the fertilizer applied should be little. By no means scatter fertilizer within the roots, so as to avoid burning the roots. In late autumn, fertilization should be controlled to prevent the autumn shoots from growing too vigorously and suffering frost damage. In winter, apply once decomposed compost or cake fertilizer and bone meal to meet the nutrient needs for new shoot growth and flowering in the coming spring. In addition, during the growing season, spray foliar fertilizer about once every 20 days, using a mixed solution of potassium dihydrogen phosphate and urea at a concentration of 0.2%-0.3%. Rixianggui cannot tolerate concentrated fertilizer or raw fertilizer; generally apply a thin, decomposed soybean cake fertilizer once every 10-15 days. For newly planted Rixianggui seedlings, by no means apply additional fertilizer; fertilizing too early will cause the plant to die.
III. Careful Pruning: Rixianggui has strong sprouting ability and tolerates pruning. The optimum temperature for flower bud differentiation is 6-8°C, and the temperature for the greatest flowering amount is 16-18°C, with air humidity at 75%-85%.
Care of Osmanthus
[Other Names] Also called Yangui, Muxi
[Family and Genus] Belongs to the Oleaceae family, Osmanthus genus
[Common Varieties] Jinguí, with golden-yellow flowers, strong fragrance, and abundant flowering, blooms every autumn; Yingui, with white to pale yellow flowers, blooms later than Jinguí, and its fragrance and flowering amount are also inferior to Jinguí; Dangui, with orange-red flowers, and its fragrance is lighter than Yingui; Sijigui, with creamy-yellow flowers and a light fragrance, but a very long flowering period. Except when it cannot open in high temperatures or severe cold, it can bloom at other times, and it is the variety most sold on the market.
[Place of Origin and Growth Habits] Native to China, with the main production areas in the southwest region and central-south region. It is a temperate flower, likes a warm and humid climate, and cannot endure a cold environment below 0°C. When the temperature is above 38°C, flowering is poor. It likes strong light; when the light is not strong (such as indoors), it only grows leaves and is difficult to flower, but slightly shading it at noon in summer is beneficial to its growth. The root system fears long-term waterlogging, and too much water rots the roots.
[Key Points for Purchase] When selecting potted osmanthus, in appearance choose products with evenly matched branches and a low branching point. At flower farms, osmanthus is mostly planted in the ground, and only when it is about to be sold is it dug up and put into pots, so for osmanthus that has been temporarily potted in this way, no matter how carefully we cultivate it after buying it home, it will drop leaves. Therefore, pay attention to choosing products with small roots extending out from the drainage holes at the bottom of the pot. For osmanthus that has just been potted, the potting soil is very fresh and very soft, and it can be distinguished with a little care. The same principle applies when selecting other woody potted flowers.
Osmanthus likes light and is slightly shade-tolerant. It likes warmth and a well-ventilated environment, is not cold-resistant, likes moist and well-drained sandy loam, and avoids waterlogged land, alkaline land and heavy, sticky soil; it has moderate resistance to sulfur dioxide, chlorine gas, etc. Osmanthus has the habit of sprouting twice and flowering twice, and consumes a large amount of fertilizer. It is suitable to apply base fertilizer in winter in November-December, so that the branches and leaves are luxuriant in the following spring, which is beneficial to flower bud differentiation; in July in summer, before the second branches emerge, applying additional fertilizer is beneficial to the sprouting of the second branches, resulting in large and dense flowers in autumn.
Osmanthus trees are rather delicate. First of all, master the water amount well, and by no means let it become waterlogged. If it is potted, pour out the water in the saucer after each watering; do not let it soak. And water it every day; in the north, if there is heating indoors, you must water it every day. You can buy some organic fertilizer, and giving it some strength should be fine. In addition, see whether the soil is very sticky and heavy and drains water very slowly, as this can also easily cause leaf drop.
Sijigui is suitable for growing in warm, humid places with sufficient sunlight. The soil in which it is planted should be fertile, loose, slightly acidic and well drained and irrigated. Sijigui is relatively drought-tolerant and cold-tolerant, and its optimum growth temperature is 20-30°C. In winter, if there is no especially severe cold wave, it can generally overwinter in the open ground. It can usually be propagated by cuttings, layering or sowing. If planted in flower beds or garden landscapes, its plant height can reach 2-3 m. If used for household potting, it can be dwarfed to below 1 m. Its trunk has many branches, and its leaves are relatively fine. After its seedlings have grown for one year, they can successively bloom, and after growing for 3 years the flower amount is even greater, with considerable ornamental value. In cultivation and management, attention should be paid to appropriately applying more phosphorus and potassium fertilizers such as plant ash and bone meal to increase the flower amount and fragrance. Also pay attention to preventing and controlling diseases and pests such as leaf spot disease, anthracnose, nettle caterpillar and wax scale, to ensure normal plant growth and development and timely flowering.
[Suitable Placement Location] According to the growth characteristics of osmanthus, it is better to place it on a southeast-facing balcony. If it must be placed indoors, also choose a southeast-facing door or window so that it can receive the maximum amount of light.
[How to Water] For potted osmanthus, from late autumn to early spring, water only after the potting soil is slightly dry or the leaves are a little wilted, and water thoroughly in one go. In the vigorous growth season from late spring to early autumn, water more frequently. If you have no experience, you can water thoroughly in one go when the leaves wilt, or wait until the surface of the potting soil turns white and has slight cracks, then water thoroughly. Generally, in high summer temperatures, you can water twice a day, once in the morning and once in the evening. Note that if the water supply is too much, it will cause flower drop. For home flower growing, controlling watering is very difficult; the most mechanical method is still not to water if it is not dry (wilted), and to water thoroughly when watering. When there is too much water, the leaves will turn yellow.
[How to Fertilize] After the beginning of spring, start fertilizing when the nighttime temperature rises back above 15°C. At this time the branches begin to grow and need fertilizer. If using compound fertilizer, the amount each time is 4 grams (about one bottle cap of a small mineral water bottle). Make four small holes around the potting soil, put the compound fertilizer in evenly, then cover with soil (change the position next time you make holes), and fertilize once every 10-15 days, until after the nighttime temperature drops below 8°C in autumn, then stop fertilizing. If applying organic fertilizers such as cake fertilizer, the amount each time is 1/3 of a rice bowl (no need to dilute with water). If it is packaged flower fertilizer bought from a flower shop, just follow the package instructions; if there are no package instructions, ask clearly. When you see flower buds growing, stop fertilizing; excess nutrients will cause bud drop (except for Sijigui).
[Adjusting Temperature] Osmanthus is somewhat afraid of cold but not of heat. It grows only when the nighttime temperature is above 15°C. For northern regions, if you want it to still bloom during the National Day period, move it indoors before autumn begins in August, keep the temperature above 15°C, and stop fertilizing and water less (water after it wilts), then move it out again for care in mid-September, so that it can bloom profusely during the National Day period.
[Preparing Flower Soil] Nowadays it is very difficult to find some flower soil in the city, so you can mix it yourself. Use 5 bowls of garden soil (obtained at a construction site), 1 bowl of yellow sand; if you can get some sawdust, all the better, add 1 bowl; if there is no sawdust, use another half bowl of yellow sand instead. This only provides a ratio. Mix these things thoroughly and evenly, and the flower soil is ready.
[How to Ventilate] The principle of ventilation is that through the natural circulation of air, it can increase the air humidity around the potted flowers, increase the carbon dioxide content around the leaves, and cycle away the air carrying pathogens around the leaves (we will notice that moldy air is mostly in closed small spaces where air does not circulate, which is very favorable to the reproduction of various pathogens. This is the same principle as "running water does not rot"), making potted flowers less likely to be infected by diseases. Today's residential rooms mostly have doors and windows tightly closed and no air circulation, especially rooms with air conditioning; to save energy, air conditioning only circulates indoor air and does not exchange it with outdoor air, so its air becomes less and less fresh and the air humidity is also very low. Therefore, it is necessary to open doors and windows for ventilation in the morning and evening, which is good for both flowers and people.
[How to Prune] Before the spring temperature rises back above 15°C, use household scissors or a sharp blade to cut or trim off dead branches, thin and weak branches, and branches with diseases or pests, to make way for new branches and at the same time not give diseases and pests a chance to reproduce. Combined with the tree shape, during the growing period, remove a small portion of unwanted newly sprouted branches, so as to concentrate the limited nutrients and make flowering more luxuriant. This is the same as with people: "Many children make the mother suffer." But note that you cannot prune all the new branches, because only new branches can produce flower buds. After the Beginning of Autumn flowering period has passed, also, combined with the tree shape, thin out part of the overly dense branches and shorten the particularly tall branches.
[Propagation Method] In early spring, when the temperature has just risen back above 15°C, cut branches without side branches into sections about 10-12 cm long, with at least three leaf nodes or bud eyes, and insert them into a flower pot filled with more than half a pot of nutrient soil, inserted 1/3 deep (about 3-5 cm), and press firmly slightly. After watering, tightly cover the pot opening with a transparent plastic bag and place in a shady spot. They will root in about 25-40 days. During this period, open the film every 5-7 days to let in some air (one hour). Generally there is no need to add water; if it is too dry, you can spray some water with your mouth.
[Pest and Disease Control] If insect pests are found, spray with household aerosol insecticide; if diseases are found, directly cut off the diseased leaves or branches.
[Post-Bloom Treatment]
[Repotting] With care according to the above methods, osmanthus can grow well. After the beginning of spring the next year, change the osmanthus into a slightly larger flower pot. First put 3 cm of nutrient soil in the bottom of the large pot, add two bottle caps of compound fertilizer and scatter it evenly; then lay the osmanthus on its side, cut off the roots outside the hole at the bottom of the pot, shake it gently a few times, then pull out the osmanthus together with the soil ball, being careful not to let it break apart, put it into the large pot, add soil while pressing firmly slightly, and water.
Osmanthus, Oleaceae. Evergreen tree, up to 10 m tall, with luxuriant branches and leaves. Leaves opposite, elliptical, with fine serrations at the leaf margin, leathery, dark green. Drupe ovoid. Flowers solitary in leaf axils, or clustered at the branch tips, white, opening in September-October, with a rich fragrance. Its delicate fragrance wafts far, rich and deep, heavily fragrant: hence there are words of praise such as "Dense leaves a thousand layers of green, when flowers bloom ten thousand points of gold," "Its clear fragrance does not blend with the common flowers," and "It alone dominates the three autumns and surpasses all fragrances."
There are many varieties of osmanthus. Generally, those with yellow-white or pale yellow flowers are called Yingui; those with yellow flowers are called Jinguí; those with orange-red flowers are called Dangui. Among them, the August osmanthus has the strongest fragrance and is the finest among osmanthus. In addition, there is Sijigui, whose fragrance is lighter but which can bloom continuously many times. It is native to southwestern and central China. It is widely planted south of the Yangtze River, with the most cultivation in places such as Suzhou, Hangzhou and Chengdu. Xianning in Hubei and Guilin in Guangxi are even more abundant producers, and it is often grown in pots in various parts of North China.
Osmanthus likes a warm and humid climate, is cold-tolerant, and is suitable for planting in sunny, well-drained sandy soil. Applying base fertilizer in winter and additional fertilizer in early summer can promote growth and flowering. It is generally propagated by layering (ground layering or air layering), cuttings or grafting.
Growth Habits of Osmanthus
Osmanthus belongs to the subtropical evergreen broad-leaved forest region. The yellow ones are Jinguí, and the red ones are named Dangui. There are those that bloom in autumn, those that bloom in spring, those that bloom in all four seasons, and those that bloom month by month," classifying osmanthus varieties. Wen Zhenheng of the same era also gave a detailed account of osmanthus cultivation, arrangement and application in his Changwu Zhi, and Chen Haozi's Huajing in the Qing Dynasty, building on predecessors, recorded osmanthus systematically, but in the end no monograph devoted to osmanthus appeared.
Osmanthus Varieties
Sijigui flowers are small and hard to photograph
Because osmanthus has long been subjected to artificial cultivation, natural hybridization and artificial selection, it has formed rich and diverse cultivated varieties. In recent years, major cities across the country have carried out extensive surveys of osmanthus resources and varieties, recorded the flowering traits of osmanthus on the spot, analyzed and compared the traits of various types of osmanthus, selected relatively stable genetic traits, and, considering traditional classification methods and applications in garden production, identified and sorted out four cultivar groups of osmanthus.
Sijigui cultivar group: blooms in all four seasons, with varieties such as "Yueyuegui," "Rixianggui," "Daye Fodingzhu," and "Chiyesijigui."
Yingui cultivar group: blooms in autumn, with flower colors pure white, milky white, and yellow-white, with varieties such as "Ziyinguí" (seed-bearing), "Jiulonggui," "Zao Yingui," "Wan Yingui," and "Baijie."
Jinguí cultivar group: blooms in autumn, with flowers lemon-yellow to pale golden-yellow, with varieties such as "Dahua Jinguí," "Dayehuang," "Huangchuan Jinguí," "Wan Jinguí," and "Yuanye Jinguí."
Dangui cultivar group: blooms in autumn, with relatively deep flower colors, orange-yellow, orange-red to vermilion, with varieties such as "Dahua Dangui," "Chi Dangui," "Zhusha Dangui," and "Kuanyehong." In each cultivar group there are some varieties worth promoting and applying, for example: "Rixianggui" and "Daye Fodingzhu" in the Sijigui cultivar group are both small shrubs, 0.5-1.5 m tall. "Rixianggui" has pale yellow flowers, and the nodes of the same branch bloom one after another, with flowers almost every day, hence the name. At present there are large numbers of mother plants in Cangxi, Sichuan. "Daye Fodingzhu" has milky white to pure white flowers, dense inflorescences, and a unique terminal inflorescence, with a flowering period continuous from spring to autumn. They have very high ornamental value, and can both be potted indoors and planted in large expanses in the open ground.
Different regions can choose different species or varieties for propagation according to different needs. For example, for the purpose of harvesting flowers, it is suitable to choose high-yield types with abundant and dense flowers, such as "Huangchuan Jinguí," "Jinguí," "Ziyinguí," "Dahua Dangui," and "Chenghong Dangui," which bloom and drop flowers neatly. For the purpose of viewing flowers and enjoying fragrance, it is suitable to choose "Dahua Dangui," "Zi Dangui," "Zhusha Dangui," "Dahua Jinguí," and "Yuanban Jinguí." For shrubs, potted plants and bonsai, it is suitable to choose "Rixianggui," "Daye Fodingzhu," "Yueyuegui," "Sijigui," "Jiulonggui," and "Liuyegui." For use as a tree or as the main landscape of a courtyard, it is suitable to choose "Dayehuang Yingui," "Jinguí," "Daye Dangui," "Dadan Jinguí," and "Chenghong Dangui."
Some osmanthus plants bear fruit, and some do not. Generally the drupe ripens in April-May of the second year. Sowing with it generally takes 5-6 years before flowering. Asexual propagation using branch cuttings, grafting and layering can flower in the same year. A Song Dynasty record says: "When the moon is about to be full, the flowers are just right; after the flowers are about to fade, the moon wanes again. Know that things in heaven and on earth alike receive the clear autumn at one time," pointing out its basic flowering pattern: that is, on the fifteenth day of the eighth lunar month each year when the moon is full, osmanthus blooms profusely; half a month later the flowers have faded and the moon has also waned.
Osmanthus likes warmth and has strong stress resistance; it is both heat-tolerant and relatively cold-tolerant. Therefore, in areas south of the Qinling Mountains and the Huai River in China, it can overwinter in the open ground.
Osmanthus relatively likes sunlight and can also tolerate shade. Under full sunlight its branches and leaves grow luxuriantly and it flowers densely; in shady places it grows sparse branches and leaves and flowers sparsely. If potted indoors in the north, especially attention should be paid to having sufficient light, to facilitate growth and the formation of flower buds.
Osmanthus by nature likes moisture, and by no means tolerates waterlogging, but it also has a certain drought tolerance.
The ancients recorded a great deal about the weather conditions for osmanthus flowering. In the Tang Dynasty, Wang Jian wrote in "Looking at the Moon on the Night of the Fifteenth": "Cold dew silently moistens the osmanthus"; Liu Zongyuan wrote "Dense dew on the osmanthus of the front mountain"; Bai Juyi wrote "Heaven steams the autumn air into cold fragrance, the moon borrows golden waves to pick the yellow seeds"; in the Song Dynasty, Lu You wrote: "Heavy dew moistens the fragrance on the quiet path at dawn, the slanting sun warms the stamens, beautiful by the small window." In the poems, "cold dew" and "dense dew" show that the flowering weather should be cool in the morning and evening; "warming and steaming" shows that the weather will also once again have relatively high temperatures. This kind of weather, cool in the morning and evening and hot during the day, is not only beneficial to the nutrient accumulation of the osmanthus tree but also promotes the formation of rain and dew, and the osmanthus tree then accelerates its flowering, which the people of Suzhou call "muxi steaming." Around the Mid-Autumn Festival the weather suddenly becomes hot, just like summer, and once the osmanthus is steamed, it blooms profusely. Osmanthus flowering requires a certain humidity and also a certain temperature difference.
Osmanthus is not very demanding about soil. Except for alkaline soil and low-lying land or overly heavy, sticky, poorly drained soil, it can generally grow, but deep, loose, fertile, well-drained, slightly acidic sandy loam is most suitable.
Osmanthus has a certain resistance to harmful gases such as chlorine gas, sulfur dioxide and hydrogen fluoride, and also has a relatively strong ability to absorb and retain dust, so it is often used for greening in cities and industrial and mining areas.
Propagation and Processing of Osmanthus
Osmanthus, also known as Muxi, is an evergreen small tree. It is a precious ornamental aromatic plant, blooming in autumn, with a clear fragrance that is deep and refreshing. Osmanthus is a specialty of China and one of China's main aromatic raw materials. Osmanthus can be used to extract aromatic oil and is a precious spice. Essences and fragranced products made with pure osmanthus oil, such as osmanthus wine, osmanthus sugar, osmanthus preserves, perfume, and scented soap, sell well in domestic and foreign markets.
1. Main Varieties. There are relatively many varieties of osmanthus, including Jinguí, Yingui, Dangui, Sijigui, and Yueyuegui. Among them, Jinguí has a strong fragrance and also bears many flowers, and has high ornamental and economic value. Sijigui has a long flowering period and will bloom except in severe winter and intense summer heat, most abundantly in autumn, but its tree form is short and small and its fragrance is relatively light, so it is only suitable for courtyard planting and viewing.
2. Propagation Methods. Osmanthus can be propagated by sowing, approach grafting, cut grafting, layering, and cuttings, generally mainly by approach grafting and cuttings. The rootstock for approach grafting is small-leaf privet; after joining, it can flower in the same year, and approach grafting is mostly carried out in summer. The cutting method can propagate large numbers of osmanthus seedlings, and the time is mostly chosen in February when the tree sap is about to flow. To promote rooting and prevent diseases, the cuttings are sprayed with 800-**** times trichlorfon solution 1 month before cutting, then disinfected with lime water 10-15 days before cutting, and immediately before cutting the base of the cuttings is soaked in a 10×10-6 naphthaleneacetic acid solution for 8-10 hours. The cuttings are inserted 2/3 deep into the soil, and immediately after cutting water thoroughly, and a certain humidity is maintained regularly; a shade net can also be set up above the seedbed. They will root in about 2 months. They are transplanted once the second year, and can leave the nursery for planting in the third year.
3. Key Points of Cultivation. Osmanthus likes dryness. Apart from paying attention to watering and moisturizing when transplanting, it generally does not need irrigation, so the soil is required to be well drained. Usually large trees put out branches once a year, and young trees put out branches 2-3 times. Fertilize once each in December, June and September each year, or before each branch growth or flowering. In the early stage of spring sprouting, heavy fertilizer should not be applied; pig and cattle manure, soybean cake, etc. are good fertilizers. From May to October, timely cultivating, loosening the soil and weeding should be carried out to maintain soil moisture and avoid weeds competing with the trees for fertilizer. Osmanthus has a well-developed root system and many fibrous roots, and strong adaptability; it is easy to survive transplanting. Generally, trees under 20 years old are easy to transplant and survive in both spring and autumn.
4. Harvesting and Processing. In September and October when the flowers are in bloom and their fragrance wafts, collect the osmanthus, mix it with alum (3.5%) and press it tight. After a few days, press out the juice so that it keeps its original flower weight, then add the same amount of sugar, mix well and put it into a jar. It can be used as the raw material for osmanthus buns, osmanthus tangyuan, osmanthus wine and osmanthus preserves. The collected osmanthus can also be extracted by maceration using petroleum ether as solvent; the extract liquid is clarified, filtered, and concentrated under normal pressure and reduced pressure, and finally de-etherified to make osmanthus concrete. The yield of osmanthus concrete is about 0.17%. By repeatedly extracting the concrete with ethanol, pure osmanthus oil can be made, which is a natural precious spice. The osmanthus residue after extraction, with an appropriate amount of osmanthus essence and white sugar added, becomes osmanthus sugar, which can be used to prepare ordinary foods.
Osmanthus blooms profusely only in the eighth lunar month, and Sijigui is the same; although it also blooms in the other three seasons, it blooms relatively little. To grow osmanthus, use moderately acidic soil for planting, such as humus soil, pine needle soil, Yuexi soil (grass-root soil) and other acid-containing soils mixed with garden soil for planting; the ratio can be 5:5 or 4:6 (acid soil: garden soil). In summer, place it where the sun cannot shine directly, with diffused light being enough. In autumn, winter and spring, place it in a place with sufficient light. Keep the moisture at moist soil. If you want many flowers and fragrant flowers, use more potassium dihydrogen phosphate to force flowering, using a 1:100 ratio, spraying once every 10 days, and for irrigation just keep to light fertilizer applied frequently. Do not fertilize in winter.
[Disease Prevention for Osmanthus Trees]
I. Identification and Control of Major Osmanthus Diseases
1. Leaf Spot Disease
The lesions occur on both sides of the leaves. In the early stage of the disease, only some scattered brown spots appear on the leaf surface; later the center of the lesion on the leaf surface is gray-white to light brown, nearly round or irregular in shape, and in severe cases several lesions merge together; the edge of the lesion is red-brown to dark brown, with a light brown halo outside, and a large number of small gray-black mold spots are scattered on the front of the leaf, which are the pathogen's conidiomata and conidia; the lesion on the back of the leaf is brown; because the lesions gradually expand and merge into large patches, they often cause a large number of leaves to wither and drop, seriously affecting the plant's normal growth and flowering. The pathogen of this disease overwinters as mycelial masses on diseased plants and fallen leaves. When the temperature rises in April-June of the following year, new conidia are produced and spread by airflow and rain, causing infection and damage, and then producing new conidia for reinfection and disease occurrence. This disease can occur from April to October; on the plant, old leaves are more affected than young leaves. Jinguí varieties are most susceptible, Yingui varieties are next, and Dangui varieties are not easily susceptible; plants that are weak in growth or transplanted in the current year are prone to the disease; under conditions of compacted, heavy soil and insufficient fertility, the disease is prone to occur; in the high-temperature and humid season of July-August, the disease can spread rapidly.
Control methods: strengthen water and fertilizer management, loosen the soil frequently, avoid soil waterlogging, promote robust plant growth and improve the plant's disease resistance; in winter thoroughly remove diseased leaves and burn them in a centralized way to reduce overwintering pathogens, which can significantly inhibit the occurrence of the disease the following year; in spring, from when the osmanthus plant sprouts and grows leaves until the leaves harden, spray once every half month with a 1:2:100 lime double-strength Bordeaux mixture to prevent the disease; in the early stage of the disease, spray with 50% carbendazim·sulfur suspension 800 solution, or spray with 50% carbendazim plus 75% chlorothalonil wettable powder 500 solution, or spray with 50% zineb wettable powder 800 solution; 25% propiconazole emulsifiable concentrate 5000-fold solution can also be sprayed, with an interval of 48 days. When seedlings from severely affected areas leave the nursery, they can be sprayed with 0.1% potassium permanganate solution for sterilization.
2. Leaf Blight
Also called leaf spot disease, it is an important disease of osmanthus. It mainly harms leaves. The lesions mostly begin at the leaf tip or leaf margin, first as yellow-green or light brown small spots, then gradually expand, becoming red-brown to gray-brown, in a nearly round or irregular shape; the color on the back of the lesion is lighter, with a dark brown edge; the lesion sometimes curls and becomes brittle and cracks, and several lesions can merge with each other to reach 1/2-1/3 of the leaf, or form irregular large patches; in the later stage, many small black grains are scattered on the lesion, which are the pathogen's pycnidia. This disease can occur throughout the year, causing large areas of leaves to dry up and leading to premature dropping; leaves in the middle and lower part of the canopy are more seriously damaged than those at the top, and old leaves are more affected than new leaves. Its pathogen overwinters as mycelium and pycnidia on diseased leaves. In spring, when temperature and humidity are suitable, it infects and causes disease with conidia, spreading by wind and rain, and is most serious from July to November; when the temperature is 20-27°C, with more rain or high humidity, poor ventilation, insufficient fertilizer, weak tree vigor, or frost damage or mechanical injury, it is prone to occur; when the climate is hot and dry and water is not applied in time, the condition worsens.
Control methods: in late autumn and early winter, thoroughly remove diseased leaves and burn them in a centralized way or bury them deeply to reduce overwintering pathogens, which can effectively inhibit the occurrence of the disease the following year; for seedlings being transplanted or introduced, remove diseased leaves and burn them in a centralized way, and if necessary, before leaving the nursery spray the seedlings with 50% carbendazim wettable powder 500-fold solution or 0.1% potassium permanganate solution for sterilization and disinfection; strengthen management, apply more phosphorus and potassium fertilizers, loosen the soil and weed frequently, prevent soil compaction or waterlogging, and in hot and dry weather water and spray in time to increase the disease resistance of the osmanthus plant; in areas with severe disease, starting from late June, spray once every half month with 70% mancozeb wettable powder 500-fold solution, or 75% chlorothalonil wettable powder 800-fold solution, or 1:2:100 lime double-strength Bordeaux mixture, for 3-4 consecutive times, with good control effect; 25% propiconazole emulsifiable concentrate 5000-fold solution can also be sprayed, with an interval of 48 days.
3. Sooty Mold Disease
It mainly appears as a layer of gray-black powdery material of varying shades covering the leaf surface and branches, sometimes even forming a black film. The reason is that when insects such as aphids, scale insects and whiteflies pierce and suck to damage osmanthus, the excretions they secrete cause various fungi to parasitize, thus inducing the dark, gray sooty mold disease. It usually occurs in high-temperature, humid seasons and in stuffy, humid, sheltered, poorly ventilated environments. The gray-black sooty mold layer not only affects the ornamental value of the osmanthus plant, but also affects the photosynthesis of the leaves, causing poor plant growth and causing infected leaves to turn yellow, wilt, and then drop prematurely.
Control methods: strengthen the shaping and pruning of the osmanthus plant, ensure ventilation and light penetration inside the canopy, and promote good plant growth; when insects such as aphids, scale insects and whiteflies are found piercing and sucking to damage osmanthus, carry out effective control in time and kill them; for potted plants, frequently spray water to wash the leaf surface; in the early stage of the disease, spray the branches and leaves with 50% carbendazim·sulfur suspension 500-fold solution, or 50% carbendazim wettable powder 800 solution, or 75% chlorothalonil wettable powder 500 solution, with relatively good control effect.
4. Chlorosis
That is, iron-deficiency chlorosis. If it is mild iron deficiency, it appears as yellowing and loss of green between the veins of young leaves, while the vein tissue remains green; if it is severe iron deficiency, it appears as yellowing of all new and old leaves, the young leaves slowly stop growing, and some old leaves show yellow-brown spots. The plant cannot grow and flower normally, seriously affecting the ornamental effect and the amount of flowers harvested. The reasons: first, ground-planted plants are affected because the soil is alkaline; second, potted plants are affected because the formula ratio used when preparing the potting soil is improper and the pH value is unbalanced; third, osmanthus planted after urban and rural demolition of illegal structures is affected because the building residue was not thoroughly cleaned up; fourth, management errors, such as the pH value of irrigation water being too high; thus causing the iron element in the soil to exist in the form of difficult-to-dissolve ferric hydroxide, which cannot be absorbed by the osmanthus root system.
Control methods: for mild iron deficiency, apply 0.5% ferrous sulfate solution to the roots, and spray 0.2% ferrous sulfate solution on the leaves; when iron deficiency is severe, apply 20-40 grams of chelated iron [F-EDTA (ferric ethylenediaminetetraacetate)] into the soil around the root zone of each osmanthus (including potted osmanthus), and at the same time spray the leaves with 0.1% chelated iron solution; in the spring new shoot growth season, spray the leaf surface with 0.2% ferrous sulfate solution once every half month; when preparing potting culture soil, use 0.5% ferrous sulfate solution to adjust its pH value to below 6.5.
5. Dieback
It mainly occurs on relatively large, newly transplanted osmanthus plants. In landscaping or large osmanthus transplanting, because of bruising during digging, scratching during long-distance transport, constriction during hoisting and planting, and accidental impact, the bark of the main trunk or large branches of the osmanthus plant is severely damaged, or large pieces of bark are lifted off, and if timely and proper protection is not provided, rain and sewage infect the wounds, inducing large-scale invasion and parasitism by fungi (such as wood-rotting fungi) and bacteria (such as soil Agrobacterium), causing the wounds to rot, the xylem to be exposed, or cankers to form, causing poor plant growth, a large number of leaves to drop, and large branches to die, and in severe cases causing the death of the whole osmanthus plant.
Control methods: for small wounds on the main trunk or large branches, apply wound healing agent in time; for smaller wounds that have already developed local or a small amount of rot, clean the wound locally until fresh xylem and phloem are exposed, then apply wound healing agent well on the fresh wound, which can promote the wound to heal as quickly as possible; for old large wounds on the trunk where the phloem has long been destroyed and the xylem has been exposed for many years, clean the rotted exposed xylem, and regularly apply lime sulfur mixture each year for antisepsis, or use two-component "cloud stone glue" after color adjustment to quickly apply on the fresh wound, and the protective effect will be better; for thick and large osmanthus plants whose main trunk has already formed a hollow, first thoroughly remove the rotted part, being careful not to destroy the isolation layer between the rotted xylem and the unrotted xylem, and fill the hollow with polyurethane foam.
II. Identification and Control of Major Osmanthus Pests
The main types of osmanthus pests include nettle caterpillars, mites, scale insects, whiteflies, Psilogramma menephron, bagworms, planthoppers, and Atractomorpha sinensis, among which mites, scale insects and whiteflies are the most serious and widespread.
1. Carmine Spider Mite
The mites that harm osmanthus are mainly the citrus red mite and the carmine spider mite, and their occurrence has been very serious in all parts of the province in recent years.
The adult carmine spider mite is 0.5-0.6 mm long; the female mite is oval, vermilion to rust-red, or dark brown to black-brown; the male mite is slightly diamond-shaped, pale yellow, slightly smaller, 0.3-0.4 mm long. The egg is round, pale red to pink. The larva is nearly round when first hatched, translucent, and its body is dark green after feeding. The nymph is oval in body shape, with a darker body color. It can occur 10-15 generations a year. In the south, it overwinters as adult mites, nymphs and eggs on host plants and weeds; when the average temperature reaches above 7°C the following spring, it begins to move, feed, reproduce and cause damage. Adult mites, larvae and nymphs all like to gather on the underside of leaves to feed, and eggs are mostly laid on both sides of the leaf veins on the underside of leaves or under dense fine silk webs. Each female mite can lay 50-500 eggs in its lifetime. The high-temperature and dry season is most favorable for its major outbreak, causing the leaves of a whole plant or a whole osmanthus grove to turn gray-yellow, seriously affecting the growth, flowering and display and viewing of osmanthus. The optimum temperature for this pest's occurrence is 25°C-30°C, and the optimum relative air humidity is 35%-55%. Strong winds and heavy rain can wash away the mites and reduce the population density.
Control methods: protect natural enemies, such as Stethorus punctillum, Orius minutus, Scolothrips takahashii, Chrysopa sinica, and Chrysopa septempunctata; in winter remove weeds under the trees and burn them, and use 0.3-0.5 degrees Baumé lime sulfur mixture to kill overwintering adult mites, nymphs and eggs; in the early stage of occurrence, spray with 25% fenbutatin oxide (main ingredient azocyclotin) 1500-fold solution; or spray with 1% abamectin emulsifiable concentrate (main ingredient avermectin) 2000-fold solution; in addition, pesticides such as hexythiazox, fenpropathrin, and mite-killing agents can also be sprayed.
2. Cottony Cushion Scale
The scale insects that harm osmanthus include red round scale, fern round scale, red wax scale, brown soft scale, cottony cushion scale, Chaff scale, Pseudaulacaspis cockerelli, snake-eye scale, arrowhead scale, Japanese long white scale, orange cottony scale, oval scale, black spot scale, and coconut round scale, etc. Among them, cottony cushion scale, Chaff scale, Japanese long white scale and orange cottony scale are quite common in damage.
Cottony cushion scale: adult body length 5-7 mm; the female is oval, orange-red, with a flat ventral side and a raised back, and before laying eggs secretes a white egg sac behind the abdomen, with 14-16 longitudinal lines on it; the male is slender and small over the whole abdomen, about 3 mm long, with a black thorax and orange-red abdomen, the forewings narrow and long, black, and the hindwings degenerated into hooks. The egg is oval, 0.7 mm long, orange-red, densely packed in the female's egg sac. The nymph is oval, orange-red, with the back covered with pale yellow wax powder. The pupa is 3.5 mm long, orange-red, with pale yellow-brown fine hairs scattered on the body, covered with a thin white waxy powder. The cocoon is long oval, white, composed of loose wax filaments, with white wax powder on the outside. This pest occurs 2-3 generations a year, with overlapping generations; most female adults gather and fix in one place, secreting a white waxy egg sac at the end of the abdomen, laying eggs while secreting wax, with an egg-laying period of more than 30 days, and each female can lay hundreds to 2000 eggs; males are few, and it mostly reproduces by parthenogenesis; after hatching, the larvae disperse and move, then migrate from tender tips and the underside of leaves to the branches and trunk to live in groups, sucking the tree's sap and excreting honeydew, inducing sooty mold disease. Because the insect and disease damage interact, it often causes osmanthus plant leaves to turn yellow and branch tips to wither.
Control methods: usually use less pesticide and protect natural enemies well; when a small number of insects are found, wipe them off and squeeze them to death in time; in winter spray 0.3-0.5 degrees Baumé lime sulfur mixture to kill overwintering pests; at the peak of egg hatching, spray with 15% buprofezin wettable powder 2000-fold solution, or spray with 40% dimethoate emulsifiable concentrate 1500-fold solution, or spray with 40% methidathion emulsifiable concentrate 3000-fold solution.
3. Tea Bagworm
Bagworms, also called "hanging ghosts." The bagworm pests that harm osmanthus include the tea bagworm, large bagworm, and small bagworm. Their common feature is that the insect body hides in a bag, and the larvae and female adults gnaw leaves and tender branches. In severe cases they can eat all the leaves of the whole plant. When high temperature and drought last a long time, the damage is even more serious.
Tea bagworm: adults are dioecious; the female adult is wingless, 12-16 mm long, maggot-shaped, obese, with a small head and a pair of spines; the male is 11-15 mm long, with a wingspan of 22-30 mm, and both body and wings are dark brown, with a transparent rectangular spot near the wing tip of the forewing and another near the center of the outer margin; the egg is oval, milky yellow-white, about 0.8 mm long; the mature larva is 10-26 mm long, with brown longitudinal bands on the subdorsal line of each thoracic segment and on the upper spiracular line of the mesothorax and metathorax, and the space between the bands is jade white; the pupa: the female is hammer-shaped, dark brown, with a small head and curved thorax, 14-18 mm long; the male is brown, 11-13 mm long, with the abdomen curved into a hook shape, each with a pair of anal spines; the protective bag is olive-shaped, dark brown, silky, up to 25-30 mm long, with fragments of branch bark and cut-off small twigs attached outside, neatly and longitudinally split in parallel. This pest occurs 2-3 generations a year and overwinters as mature larvae; adult emergence often occurs in the afternoon, and mating occurs the next evening; after emergence the female still stays in the bag, and after emergence the male flies near the female's bag to mate; eggs are laid inside the bag, with each female laying about 500 eggs; after hatching, the larvae crawl from the bag's excretory opening to the branches and leaves, spin silk and hang down, and spread with the wind to surrounding hosts to feed, using silk to tie leaves and small twigs together to make a protective bag; when the larva crawls to feed, the head and thorax are exposed outside the bag, and the bag hangs at the abdomen; feeding time is mostly in the early morning, evening or on cloudy days, and it rarely feeds at noon on sunny days; in the early stage it feeds on the leaf mesophyll, leaving the epidermis as transparent spots; as the larval age increases, it eats the leaves into holes and notches; when there are many insects, they can eat all the leaves of the whole plant and gnaw the bark, flowers and fruits.
Control methods: manually remove the protective bags and eliminate the larvae; protect natural enemies well; use black light lamps and frequency-vibration lamps to trap and kill adults; spray 2 billion/g cotton bollworm nuclear polyhedrosis virus suspension 1000-fold solution at the peak of egg laying; at the peak of second-instar larvae, spray 90% trichlorfon crystal 1000-fold solution, 40% dimethoate emulsifiable concentrate 1000-fold solution, 1.2% nicotine·matrine 1000-fold solution, or diflubenzuron No. 3 1000-2000-fold solution for control.
3. Psilogramma menephron
The adult is 45-50 mm long, with dark gray body and wings mixed with frost-like white powder; wingspan 90-130 mm, with brownish semi-circular stripes on the thoracic notum, two brownish wavy horizontal lines in the middle of the forewing, two black longitudinal lines below the discal cell, and a black curve at the wing apex; the hindwing is brownish, and the outer margins of both forewings and hindwings are formed by small black-and-white alternating square spots connected together. The egg is spherical, green when first laid, later turning yellow. The larva is green, 75-96 mm long, with a pale green head, green thorax, and 8-9 rows of transversely arranged granules on the back; the abdomen is yellow-green, with 7 white diagonal bands on the sides; the tail horn is brown-green, with purple-brown granules on it, 12-13 mm long; the spiracles are brown, the thoracic legs yellow-brown, and the abdominal legs green. The pupa is red-brown, 50-60 mm long. This pest occurs 3 generations a year in the Yangtze River basin, overwintering as pupae in the soil. The moth period of the overwintering generation is from early to mid-April to late July, the first generation from mid-to-late July to early-to-mid September, and the second generation from mid-to-late September to early October. Adults rest during the day hidden in the dark places of trees, branches and leaves, weeds, crops and buildings, and fly out at dusk to be active; mating and egg laying both occur at night; they have strong flying ability and relatively strong phototaxis; adults mostly lay eggs on the underside of leaves; newly hatched larvae feed on the leaf surface layer, and when slightly larger gnaw the leaves into notches and holes, and may even eat all the leaves; mature larvae enter the soil to pupate.
Control methods: turn the soil in winter to kill overwintering pupae; use black light lamps to trap and kill adults; if Psilogramma menephron larvae appear on a small number of individual osmanthus plants, they can be manually captured and killed; before the 3rd-instar larvae, spray 90% trichlorfon crystal 1000-fold solution, 40% dimethoate emulsifiable concentrate 1000-fold solution, or 10 billion/g Bacillus thuringiensis spore powder 500-fold solution.
4. Latoia lepida
Nettle caterpillars, that is, "yanglazi." The nettle caterpillars that harm osmanthus include the yellow nettle caterpillar, Latoia lepida, Setora postornata, Thosea sinensis, and Latoia pastoralis. Their larvae can sometimes eat all the leaves of osmanthus and other plants, causing the affected branches to wither, hindering the growth of osmanthus, and reducing the ornamental and economic value of the flowers and trees.
Latoia viridissima adult: body length 16-18 mm, emerald green, with one quadrangular dark brown spot at the wing base; hindwings light brown. Egg: oval, 0.9-1 mm, yellow-green. Larva: when fully grown, body length about 24 mm, body emerald green, head reddish brown, with 3 longitudinal bands of blue-purple and dark green along the center of the back, blue patches and stinging branches on the back, a pair of orange-red stinging spines on the back of the first abdominal segment, and a black pom-pom-like tuft of hairs at the end of the abdomen. Pupa: oval, 14-17 mm long, yellow-brown; cocoon: dark brown, flat, covered with white silk, oval, 14-17 mm long. In the Yangtze River basin this insect has 2-3 generations per year, overwintering as fully grown larvae in cocoons on branches and trunks; the following year it pupates from April to May, and the first and second generations of adults emerge and lay eggs from mid-May to early June and from early August to mid-September. Adults are strongly phototactic, mate on the night of emergence, and begin laying eggs the next day; a single female can lay 600-900 eggs. Eggs are laid in numbers from a few to more than a hundred, mostly 30-40, concentrated on the undersides of young leaves and arranged like fish scales. Newly hatched larvae feed only on the leaf mesophyll and lower epidermis, leaving the upper epidermis; after the 3rd instar they bite through the epidermis, and after the 5th instar they feed on the entire leaf. Larvae have 7 instars in total, like to gather in groups, and gradually disperse after the 5th instar. Fully grown larvae spin cocoons in bark crevices and at the base of the trunk, and some first-generation larvae spin cocoons on the undersides of leaves.
Control methods: Check Osmanthus plants promptly for white to semi-transparent damaged leaves; for leaves with large numbers of larvae, wear gloves and remove and kill them promptly to prevent being stung by their venomous hairs; manually scrape off overwintering cocoons on branches and trunks, which can reduce the overwintering population and prevent severe outbreaks the following year; use blacklight traps to kill emerged adults and reduce the number of next-generation larvae; during the larval stage, use biological pesticides such as Bacillus thuringiensis and Bacillus cereus; during the larval occurrence period, spray to kill larvae with 90% trichlorfon crystal at 1000 times dilution, 0.3% azadirachtin emulsifiable concentrate at 600 times dilution, 1.25% matrine-nicotine at 1000 times dilution, and 1.2% diflubenzuron at 8000 times dilution.
5. Whiteflies
The main whitefly pests damaging Osmanthus include greenhouse whitefly, orange-yellow whitefly, orange spiny whitefly, orange green whitefly, and Osmanthus whitefly (in Hefei, Chuzhou, and Wuhu cities). They mainly use the mouthparts of adults and larvae to pierce the leaf mesophyll on the undersides of leaves and suck sap, causing Osmanthus leaves to curl, fade to yellow, and even dry up; the large amount of honeydew they excrete seriously contaminates Osmanthus branches and leaves and can trigger sooty mold, causing poor growth of Osmanthus and thereby affecting normal flowering and display for viewing.
Control methods: Protect natural enemies, such as Amitus spiniferus, long-abdomen wasps that prey on whiteflies, black spiny whitefly wasps, yellow Encyrtidae wasps, green lacewings, ladybugs, chalcid wasps, predatory mites, and so on; greenhouse whitefly adults can be trapped and killed with yellow sticky traps; whiteflies have strong pesticide resistance, so when choosing pesticides for control, adhere to the principle of alternating and mixing them, for example, 10% buprofezin emulsifiable concentrate at 1000 times dilution, 10% imidacloprid wettable powder at 2000 times dilution, 40% omethoate emulsifiable concentrate at 1500 times dilution, 25% buprofezin wettable powder at 2000 times dilution, and 20% fenvalerate at 2000 times dilution can be used alternately.
After checking the information, the branching characteristic of Osmanthus is that a branch grows to the top with few branches. To make a dwarf tree form, the main trunk must be cut off (my plant's main trunk is about 23 cm high), then the side branches below it should be bent horizontally and their tops cut, also about 20 cm long, spreading out on all sides, so that new branches on the horizontal side branches grow vertically upward, forming a hemispherical crown. In one year it sends out new branches twice, in spring and autumn, each time about 20 to 30. When the new branches are small and thin, do not apply fertilizer; wait until they have grown fully before fertilizing. Fertilizer should be applied frequently, but not in strong concentration.