Kalanchoe Propagation Methods and Solutions for Root Rot and Blackening

 How does kalanchoe reproduce? If it could not reproduce, would it not become extinct? What should be done when root rot and blackening of the roots occur during kalanchoe cultivation? Let's take a look together with Women's Web:

What are the propagation methods for kalanchoe?

Stem cuttings

So-called “stem cuttings”? This means first cutting a healthy top bud from the kalanchoe plant, about 5 to 6 cm in length. After the “wound” on the top bud has healed, insert it into the growing medium. Be sure to keep the soil moist. After about 2 weeks, once roots have developed, fertilization can begin.

Leaf cuttings

For leaf cuttings, select a complete, plump kalanchoe leaf and cut it off. Place the cut leaf in a cool, shady place for about half an hour until the cut surface has dried and healed. Then insert it shallowly or lay it flat on well-aerated sandy soil, keeping the sand semi-moist, not too wet, otherwise the leaf will easily rot. If the surrounding air is dry or somewhat cold, it is best to wrap it with transparent cling film to retain moisture and warmth, then find a place with soft sunlight and good ventilation. Roots can form within one month, and sprouts will appear in about four months.

Precautions for kalanchoe:

Kalanchoe is fairly drought-tolerant, so it does not need frequent watering. Simply water thoroughly once every 3 to 4 days and keep the potting soil slightly moist. In winter when temperatures are too low and during the summer rainy season, water volume must be controlled even more to prevent the roots of kalanchoe from rotting.

Kalanchoe prefers sunlight. If grown as an indoor potted plant, it is best placed in a spot that receives sunlight. However, by midsummer it should not be exposed to scorching sun; it can be placed in a spot with sunlight but not intense sunlight, otherwise the leaves and flowers of kalanchoe will turn yellow under strong light. If placed in a dark spot, not only will the leaves easily drop, but it also will not bloom.

Kalanchoe needs cold protection in winter. Indoor temperatures must not fall below 12°C. If the temperature is too low, the leaves of kalanchoe will gradually turn red, and the flowering period will be delayed or the plant may fail to bloom.

What should be done if kalanchoe has root rot and blackening?

Kalanchoe greatly prefers dryness and dislikes moisture. If it has been overwatered, simply move the kalanchoe to a sunny place, let the water evaporate, and let the soil become somewhat dry.

Reasons why kalanchoe does not bloom:

1. Light: Kalanchoe likes a sunny, well-lit environment. At noon in midsummer, avoid strong sunlight and scorching exposure. At other times, it can be placed in a sunny spot. It needs at least 4 hours of direct light each day to grow vigorously. To make the kalanchoe plant bloom evenly, attention should be paid to frequently changing the direction of the flowerpot so the plant receives light evenly. On building balconies, the flowerpot should be rotated 180 degrees every half month.

Although it can also grow in semi-shade, the stems will be thin, the leaves thin, the flowers few and the color pale, far less lush than in a sunny spot. If it is too shady, it will not only easily drop leaves and fail to bloom; even a plant that has already bloomed, if placed in shade, will have its flower color become dull and then the flowers will drop and wither.

2. Fertilizer nutrients: Kalanchoe likes fertilizer. Kalanchoe has a long flowering period, so the rule of not fertilizing during the flowering period should be broken. Apply a dilute nitrogen-phosphorus-potassium fertilizer or a 0.2% potassium dihydrogen phosphate solution once a month so that later flowers do not become smaller and paler due to lack of fertilizer.

From the time kalanchoe is brought indoors at Frost's Descent until October of the following year is exactly the late stage of flower bud differentiation and the peak flowering period of kalanchoe, so its demand for fertilizer is great. Before flowering, apply a phosphorus- and potassium-based fishy fertilizer once a week to promote flower bud differentiation. During the flowering period, mainly apply quick-acting potassium dihydrogen phosphate, with a concentration of 2%, once every 10 days.

What should be done if kalanchoe does not bloom:

Kalanchoe is a plant that likes light and fertilizer. Therefore, during kalanchoe cultivation, sufficient light and fertilizer must be provided, otherwise kalanchoe will not bloom. The root and stem parts of some kalanchoe varieties will naturally age after two years, and may even become withered and rotten. Because kalanchoe propagation is relatively simple, and both stem cuttings and leaf cuttings can easily propagate it, we suggest that flower lovers plant vigorous kalanchoe that is 1-2 years old.

How many times does kalanchoe bloom in a year:

Kalanchoe likes a warm, slightly humid and sunny environment. It is not cold-tolerant. The suitable growth temperature is 15-25°C. In summer, when high temperatures exceed 30°C, growth is hindered. In winter, the indoor temperature needs to be 12-15°C. Below 5°C, the leaves turn red and the flowering period is delayed. During the winter and spring flowering period, if the room temperature exceeds 24°C, flowering will be inhibited. If the temperature is around 15°C, kalanchoe will bloom continuously.

Kalanchoe is drought-tolerant and not strict about soil, preferring fertile sandy loam. Kalanchoe is a short-day plant and is relatively sensitive to photoperiod. For plants with good growth and development, giving short-day treatment (8-9 hours of light per day) for 3-4 weeks can cause flower buds to appear and bloom. Therefore, the flowering period of kalanchoe is from December to May of the following year. As long as it is well cared for, it will continuously produce beautiful flowers during this period.

Sometimes I feel that these flowers and plants really are troublesome little goblins. You have to care for them carefully and also pay attention to changes. These are the problems encountered during the growth of kalanchoe. Have you mastered them yet?

Kalanchoe cultivation methods, kalanchoe propagation knowledge

Kalanchoe has a flowering period lasting more than 4 months, producing brilliant and eye-catching flowers from December each year to April of the following year. Each flowering branch can bear as many as dozens of flowers, and the name kalanchoe comes from this.

Kalanchoe likes a warm, slightly humid and sunny environment.

Kalanchoe must not be grown in heavy, sticky soil, otherwise it will lead to poor growth, root rot and leaf drop, and in severe cases cause plant death. The potting soil should be mixed with 4 parts leaf mold, 4 parts garden soil, 2 parts river sand, plus a small amount of bone meal. This growing medium is loose and fertile, has good drainage, and shows a slightly acidic reaction, which is beneficial to root development.

Kalanchoe must not be grown in heavy, sticky soil, otherwise it will lead to poor growth, root rot and leaf drop, and in severe cases cause plant death. The potting soil should be mixed with 4 parts leaf mold, 4 parts garden soil, 2 parts river sand, plus a small amount of bone meal. This growing medium is loose and fertile, has good drainage, and shows a slightly acidic reaction, which is beneficial to root development.

During the peak growth season, apply a dilute compound liquid fertilizer once every 15-20 days to promote vigorous growth and abundant flowering. After flower buds form in November, apply 1-2 additional applications of 0.2% potassium dihydrogen phosphate or 0.5% calcium superphosphate, which will result in more flowers, brighter colors and a longer flowering period.

Like other succulent flowers, kalanchoe contains relatively more water in its body and has strong drought resistance, so it does not need large amounts of watering. During the growth period, simply water thoroughly once every 2-3 days and keep the potting soil slightly moist. When temperatures are low in winter, watering must be controlled even more. If watered too much, drainage is poor, and the potting soil is too wet, it easily leads to root rot.

1. When cultivating kalanchoe, if light is insufficient for a long time, not only will the branches become slender and the leaves thin and small, affecting the beauty of the plant shape, but the number of flowers will also decrease, the flower color will be less vivid, and a large number of leaves will drop, causing it to lose ornamental value.

2. Kalanchoe has phototropism, so during the growth period attention should be paid to frequently changing the direction of the flowerpot and adjusting the light so that the plant receives light evenly and the branches develop symmetrically in all directions. If the pot is not turned for a long time, the plant will grow toward one side, affecting the ornamental effect.

3. During the vigorous growth period of kalanchoe, attention should be paid to pinching the growing tips to promote branching, so that it has good flowers and lush leaves and does not lose its ornamental value.

1. Cutting selection is the basic prerequisite for ensuring high-quality potted flowers. For cuttings used in hydroponics, the most ideal choice is a healthy, strong, plump top bud about 10 to 15 cm long, with 2-3 nodes and more than 3-4 pairs of leaves. It is best to cut between the nodes or about 1 cm below a node. The cut surface should be slanted at about a 45° angle to form the largest possible cross-sectional area. If the top bud is a flowering branch, cut off the spent flowers. It is best if there is more than 1 cm of stem below the cutting. If it interferes with the insertion hole, the lowest pair of leaves may be removed, while the remaining leaves should be retained as much as possible.

2. The cut wounds on the branches, top buds and leaf stalks used before hydroponics must be naturally air-dried for more than 4 hours. This is determined by the characteristics of succulent and pulpy plants; otherwise the wounds easily blacken and rot, causing rooting failure. Generally, when taking cuttings of herbaceous and woody plants, they must not be dehydrated for too long, to avoid air entering the vascular bundles and blocking water transport. Therefore, herbaceous and woody cuttings should be planted after only a brief drying. If the leaves are wilting, it is best to soak them so the branches and leaves become firm again, indicating that water transport is unobstructed, before proceeding to the next step.

For kalanchoe cuttings, remember that before planting they must absolutely not be soaked in water. Instead, they need a certain degree of air-drying. Even if the leaf skin wrinkles and wilts, it does not matter; on the contrary, they root more easily. For kalanchoe branches mailed from elsewhere, no moisture-retention treatment is needed. After several days of transport, the wounds will naturally dry and shrivel upon arrival, and at this point they are very good for planting. Do not overdo it, as with herbaceous flower cuttings, by cutting off the dry parts and then soaking them in fungicide or rooting solution. In the south, where air humidity is high, I generally cut them the night before and plant them the next day or the day after.

Is kalanchoe a succulent plant? Kalanchoe cultivation methods

Is kalanchoe a succulent plant? Yes, kalanchoe is a succulent plant in the Crassulaceae family, Kalanchoe genus. It produces brilliant and eye-catching flowers from December to April of the following year, and is very beautiful. Below, follow the editor to look at an introduction to kalanchoe and kalanchoe cultivation methods.

Is kalanchoe a succulent plant?

Kalanchoe is a succulent plant, forming low clumps from plump, glossy leaves that remain emerald green all year round. In spring, summer and autumn it is planted in open ground as a border material, and from December to April of the following year it produces brilliant and eye-catching flowers. Each flowering branch can bear as many as dozens of flowers, and the flowering period lasts more than 4 months. The name kalanchoe comes from this.

Kalanchoe is a succulent plant in the Crassulaceae family, Kalanchoe genus, forming low clumps from plump, glossy leaves that remain emerald green all year round. In spring, summer and autumn it is planted in open ground as a border material, and from December to April of the following year it produces brilliant and eye-catching flowers. Each flowering branch can bear as many as dozens of flowers, and the flowering period lasts more than 4 months. The name kalanchoe comes from this. It is an ideal potted flower for giving to relatives and elders during New Year's Day and the Spring Festival.

Introduction to kalanchoe

1. Morphological characteristics

Kalanchoe is a perennial succulent herb. The stems are upright, and the plant height is 10-30 cm. The leaves are fleshy, opposite, elliptical-oblong, dark green and glossy, with a slight red tinge along the edges. In round pots, the plant bears a conical cyme, with flower colors including crimson, peach red, orange red, yellow, orange yellow and white. The corolla is long-tubular, slightly swollen at the base, and the flowering period is from December of the previous year to the end of April.

Evergreen perennial herbaceous succulent plant. Stems upright, plant height 10—30 cm. Single leaves opposite, ovate, 4-8 cm long, 2-6 cm wide, fleshy; the upper leaf margin has wavy blunt teeth, the lower part is entire, bright green, glossy, with a slight red tinge along the leaf edge. Paniculate cyme, upright, inflorescence 7-10 cm long. Each plant has 5-7 inflorescences, bearing 60-250 flowers. Flowers small, salverform, flower diameter 1.2-1.6 cm, petals 4, flower colors pink, crimson or orange-red. Kalanchoe flowering period is January-April.

2. Ecological habits

Kalanchoe prefers relatively warm temperatures. The suitable growth temperature is preferably no more than 30 degrees during the day and no less than 18 degrees at night. Temperatures that are too high or too low will affect its normal growth.

Kalanchoe is native to Africa and likes a warm, slightly humid and sunny environment. It is not cold-tolerant. The suitable growth temperature is 15-25°C. In summer, when high temperatures exceed 30°C, growth is hindered. In winter, the indoor temperature must not be lower than 12°C, and it is best at 15-18°C during the day and above 10°C at night. Below 5°C, the leaves turn red, and the flowering period is delayed or the plant cannot bloom normally, affecting holiday display. During the winter and spring flowering period, if the room temperature exceeds 24°C, flowering will be inhibited. If the temperature is around 15°C, kalanchoe will bloom continuously.

Kalanchoe is drought-tolerant and not strict about soil, preferring fertile sandy loam. Generally, repot once each spring after flowering. The potting soil is best mixed with 4 parts leaf mold, 4 parts garden soil, 2 parts river sand, plus a small amount of additional material. Kalanchoe is a short-day plant and is relatively sensitive to photoperiod. For plants with good growth and development, giving short-day treatment (8-9 hours of light per day) for 3-4 weeks can cause flower buds to appear and bloom.

Kalanchoe has a relatively low water requirement. Finish watering before noon, and the leaves must remain dry before nightfall. As a short-day plant, it will bloom only after at least 6 weeks of treatment. During short-day treatment, there must be at least 14 hours of darkness each day. Generally, October 1 each year to March 1 of the following year is the natural short-day period. For those planted in larger pots, long-day treatment should be given in the early growth stage, so that after the plant reaches a certain size it can be given short-day treatment to make it bloom. Otherwise, the plant may be on the small side.

Kalanchoe is generally not pinched in Europe and America, but in China it can be pinched as needed. Plants after pinching generally have a better plant shape. Single plants grown in flowerpots of more than 15 cm should be pinched, generally 3-4 weeks after planting. When flower buds first appear, removing some buds can promote the formation of more flower buds. After flowering, remove the spent flowers promptly.

The kalanchoe plant is compact, with dense emerald green leaves and richly colored flowers. Because its flowering period is close to Christmas and the flowering period is long, it has become a “holiday flower” used to set off the festive atmosphere. In addition, the leaves of kalanchoe are thick and fleshy, densely dark green and glossy, with high ornamental value. When it is not flowering, its leaves can still be enjoyed, making it a very ideal indoor potted flower.

Kalanchoe cultivation methods

1. Cultivation techniques

1. Planting

Plant or repot and change soil in spring. In southern regions it can be planted in the ground and overwinter outdoors; in northern regions it is suitable for pot cultivation and overwintering indoors. For ground planting, plant in a sunny place with slightly higher terrain and convenient drainage, with loose sandy loam soil. For potting soil, use fertile sandy loam. The mixing ratio of leaf mold, coarse sand and rice husk charcoal is 2:2:1. When planting, place tiles at the bottom of the pot, and mix decomposed organic fertilizer into the growing medium as a base fertilizer. Do not water immediately after planting; wait several days before watering, to avoid root rot.

2. Light and temperature

Kalanchoe is a short-day plant and is not strict about light. It can grow well under full sun, half sun and scattered light conditions. The suitable growth temperature is 15-25°C. In hot summer, pay attention to ventilation and shading, and avoid direct strong sunlight. In winter, move it into a greenhouse or place it in a sunny spot indoors, keeping the temperature above 10°C. The lowest temperature must not be lower than 5°C. When the temperature is low, the leaves easily turn red. For plants with good growth and development, after short-day treatment (8-9 hours of light per day, with shading for the rest of the time, flower buds can form in 20-30 days).

3. Watering and fertilization

Kalanchoe is a succulent plant, containing much water in its body, and is relatively drought-tolerant. During the growth period, do not water too much. Water once every 2-3 days, and keep the potting soil preferably moist but on the dry side. If the potting soil is too wet, it easily causes root rot. Follow the principle of “water when dry, water thoroughly when watering”. In winter, watering should be reduced and fertilization stopped. During the growth period, apply a dilute phosphorus-rich liquid fertilizer 1 or 2 times a month. Fertilize during the peak growth seasons in spring and autumn and after flowering.

4. Planting tips

Kalanchoe is not particularly difficult to cultivate. Choosing varieties with colorful and long-lasting flowers (kalanchoe) is very beneficial. After flowering has ended, many people discard the plant, but this is actually unnecessary. Simply cut off the flower heads, reduce water and give the kalanchoe a rest, then restore normal care. It should bloom naturally again in spring. Professional growers force kalanchoe to bloom all year round (this kalanchoe is a short-day plant).

5. Cultivation management

After potting, it grows more vigorously in a slightly humid environment, and pale red aerial roots are continuously produced at the internodes. If it is too dry or the temperature is on the low side, growth slows, the leaves turn red, and the flowering period is delayed. In midsummer, control watering and pay attention to ventilation. If it is hot and humid, the leaves easily rot and drop. During the growth period, fertilize once every half month; a “Huizhi” 15-15-30 special fertilizer for potted flowers can also be used. To control plant height, pinch 1-2 times to promote more branching and more flowering. Two weeks after planting kalanchoe, spray once with 0.2% daminozide, and spray again when the plant height reaches 12 cm. This can effectively control plant height and achieve the effect of beautiful plant shape, green leaves and abundant flowers. During the process of flower bud formation in autumn, apply 1-2 additional phosphorus-potassium fertilizers.

At the same time, during the cultivation of kalanchoe, short-day treatment can be used to regulate the flowering period, achieving the goal of supplying potted flowers year-round.

2. Key points of cultivation management

1. The pot should be small and well-ventilated; loose sandy loam is best for planting

Kalanchoe grows best when planted in well-ventilated earthenware pots, but these are not attractive indoors. They can be placed inside a plastic or porcelain pot, or planted directly in a small purple clay pot or plastic pot. When planting, place a layer of crushed charcoal pieces or crushed hard plastic foam pieces at the bottom of the pot to enhance ventilation. For pots with an inner diameter of 10 cm to 20 cm, plant 3 to 6 plants. Although it is not very selective about soil, it easily rots in heavy clay, and grows best in loose, fertile, slightly acidic sandy loam. For home potting, it is best to mix leaf mold and vegetable garden topsoil in equal amounts, then add 5% to 8% sand as the growing medium. When planting, add a little bone meal or nitrogen-phosphorus-potassium compound fertilizer as a base fertilizer.

2. Moderate water control for lush leaves; more phosphorus and potassium fertilizer for vivid flower color

Kalanchoe is a succulent plant, containing relatively much water in its body, so it is relatively drought-tolerant and afraid of waterlogging. Under the dry air conditions of high-rise buildings, it grows well. In spring and autumn, water thoroughly once after the potting soil dries, about every 3 days, and usually keep it slightly moist. In summer, water less, preferably once every 5 to 7 days. For kalanchoe placed outdoors, avoid rain during the rainy season; too much water easily causes root rot, leaf drop and even death. With appropriate water control and potting soil kept dry-wet alternately, the branches will be lush, the leaves abundant and the flowers numerous. After bringing it indoors in winter, it is best to water at noon with water close to room temperature, about once a week.

Kalanchoe likes fertilizer. Half a month after young seedlings are potted, or half a month after old plants are divided, apply 2-3 times a nitrogen-based liquid fertilizer to promote stem and leaf growth. After flowering, apply one nitrogen-based liquid fertilizer to promote recovery. At other times, except for stopping fertilization in summer, only nitrogen-phosphorus-potassium compound fertilizer should be applied. When fertilizing, do not get fertilizer on the leaves, otherwise the leaves easily rot. If the leaf surface is accidentally soiled, rinse it off with water. Kalanchoe has a long flowering period, so the rule of not fertilizing during the flowering period should be broken. Apply a dilute nitrogen-phosphorus-potassium fertilizer or a 0.2% potassium dihydrogen phosphate solution once a month so that later flowers do not become smaller and paler due to lack of fertilizer.

From the time kalanchoe is brought indoors at Frost's Descent until October of the following year is exactly the late stage of flower bud differentiation and the peak flowering period of kalanchoe, so its demand for fertilizer is great. Before flowering, apply a phosphorus- and potassium-based fishy fertilizer once a week to promote flower bud differentiation. During the flowering period, mainly apply quick-acting potassium dihydrogen phosphate, with a concentration of 0.2%, once every 10 days.

3. It likes sunlight and tolerates semi-shade; it fears severe summer heat and winter cold

Kalanchoe likes a sunny, well-lit environment. Except for slight shading at noon in midsummer, it should be placed in a sunny spot at other times. It needs at least 4 hours of direct light each day to grow vigorously. To make the kalanchoe plant bloom evenly, attention should be paid to frequently changing the direction of the flowerpot so the plant receives light evenly. On building balconies, the flowerpot should be rotated 180 degrees every half month. Although it can also grow in semi-shade, the stems will be thin, the leaves thin, the flowers few and the color pale, far less lush than in a sunny spot. If it is too shady, it will not only easily drop leaves and fail to bloom; even a plant that has already bloomed, if placed in shade, will have its flower color become dull and then the flowers will drop and wither.

To grow kalanchoe well, it is necessary to create a small environment that is warm in winter and cool in summer. At noon in midsummer, avoid strong sunlight and scorching exposure, and place it in a semi-shady spot with sufficient scattered light, such as under a large tree, under eaves or on a north-facing balcony. Pay special attention to ventilation and cooling. Water can be sprinkled on the nearby ground, but not on the plant. After the Beginning of Autumn, from late August to early September, gradually expose it to sunlight, and from October onward it should receive more sunlight to promote the transition from vegetative growth to reproductive growth. When the minimum temperature drops to around 10°C, move it indoors and place it in front of a south- or west-facing windowsill so it gets more sunlight, keeping it at 10°C at night and 15-18°C during the day. It can then bloom in December.

4. Cuttings and division are easy to propagate; pinching promotes more branching

Kalanchoe is not strict about soil. For potting, use loose sandy loam or peat soil mixed with a small amount of base fertilizer. During the growth period, fertilize once every 3-4 days to promote vigorous growth. Both compound chemical fertilizers and fermented organic liquid fertilizers can be used. In summer, when it is hot and humid, water less and stop fertilizing. After flower buds form, it is best to apply one relatively concentrated organic fertilizer or compound chemical fertilizer.

In this way, the flowers will be numerous, brightly colored and long-lasting. In the early stage of vigorous growth, pay attention to pinching to promote branching and make the potted plant fuller. Kalanchoe likes sufficient sunlight. In cultivation throughout the four seasons, it should be placed in a spot with direct sunlight. It is drought-tolerant, and will not die from dryness if not watered for three or five days.

3. Key points for early summer management

As summer begins, environmental conditions such as temperature, light and humidity change compared with spring. In order to produce high-quality kalanchoe, growers should pay attention to greenhouse production management and make corresponding adjustments when necessary.

1. Light

May and June are a stage when long and short days alternate, and day length gradually changes from short to long. For kalanchoe, a plant relatively sensitive to light, supplemental lighting should be stopped in time to avoid causing leggy growth. In order to create a short-day environment for kalanchoe, the greenhouse can be shaded. Shade from 5 to 6 in the afternoon, and uncover the shade net at 8 in the morning.

In terms of light intensity, kalanchoe is a light-loving plant, and the suitable light level is 30,000 to 40,000 lux. Too strong light will scorch the plant, but too little light intensity easily causes leggy growth.

2. Temperature

The suitable temperature for kalanchoe growth is 17°C to 27°C. When summer temperatures are too high, the plants should be shaded, otherwise it will harm them. Choose a shade net with a shading rate of 60% to 70%. If the shading rate is too high, it also easily causes leggy growth.

3. Fertilizer and water management

In this season, fertilization of kalanchoe should follow the principle of “water frequently, apply less nitrogen fertilizer”. During the seedling stage, nitrogen, phosphorus and potassium fertilizers should be balanced. After entering the flowering induction period, phosphorus and potassium fertilizers should dominate, and the amount of nitrogen fertilizer should be reduced. Applying nitrogen fertilizer lightly can effectively control the leggy growth problem of kalanchoe and improve stress resistance and disease resistance.

Now is the best stage for kalanchoe cutting propagation. However, because temperatures are relatively high now and the greenhouse easily becomes dry, the amount and frequency of misting for cuttings should be increased to keep the medium moist, which is beneficial for rooting.

In terms of watering, because summer temperatures are high, plant transpiration increases, and the evaporation rate of water in the potting soil also increases, so the watering frequency should be gradually increased to provide sufficient water for healthy growth. For kalanchoe showing leggy growth, plant growth regulator chlormequat can be applied for regulation, and it is best to apply it under moist soil conditions. Soil that is too dry or too wet is not conducive to the plant's absorption of the chemical.

4. Pest and disease control

As the weather warms, both temperature and humidity in the greenhouse increase, and pest and disease control becomes a problem that cannot be ignored in this season's kalanchoe management. Therefore, growers must pay attention to pest and disease prevention, routinely disinfect the greenhouse, and regularly spray protective fungicides.

Kalanchoe is very susceptible to pest infestation. Common pests include thrips, red spider mites, snails, slugs, aphids, noctuid moths, cabbage caterpillars and so on. For these pests, prevention should be the main approach, with strict control at greenhouse vents and entrances and exits to prevent pests from entering the greenhouse.

Kalanchoe is a relatively “tough” flower with few diseases. Common diseases mainly include downy mildew and anthracnose, which can be controlled by spraying fungicides such as carbendazim and mancozeb.

5. Kalanchoe care tips

The kalanchoe plant is small and exquisite, compact in shape, with emerald green leaves and dense flowers. It is an ideal indoor potted flower for winter and spring. Its flowering period coincides with Christmas, New Year's Day and the Spring Festival, making it very suitable for decorating windowsills, desks and table tops. Used in flower troughs, display windows and halls in public places, its overall ornamental effect is excellent. Because of the name “longevity,” giving a pot of kalanchoe to relatives and friends during festivals is also very appropriate and likable, symbolizing great fortune and longevity.

Kalanchoe likes sufficient sunlight. For home cultivation, it should be placed in a spot with direct sunlight throughout the four seasons. However, around noon in summer, it should be appropriately shaded and can be moved indoors, otherwise the light is too strong and easily makes the leaf color turn yellow. Conversely, if light is insufficient, not only will the branches be weak and slender, the leaf surface thin and the plant shape unattractive, but the number of flowers will also decrease, the flower color will be less vivid, and a large number of leaves will drop, losing ornamental value.

Kalanchoe is drought-tolerant and not strict about soil, preferring fertile sandy loam. Generally, repot once each spring after flowering. The potting soil is best mixed with 4 parts leaf mold, 4 parts garden soil, 2 parts river sand, plus a small amount of additional material. Kalanchoe is a short-day plant and is relatively sensitive to photoperiod. For plants with good growth and development, giving short-day treatment (8-9 hours of light per day) for 3-4 weeks can cause flower buds to appear and bloom.

Kalanchoe is drought-tolerant, so it does not need large amounts of watering. Simply water thoroughly once every 3-4 days and keep the potting soil slightly moist. In winter when temperatures are low and during the rainy season, watering should be controlled to avoid root rot.

During the peak growth season, apply a dilute compound liquid fertilizer once every 2-3 weeks to promote vigorous growth and abundant flowering. After flower buds form in November, apply 1-2 additional applications of 0.2% potassium dihydrogen phosphate or 0.5% calcium superphosphate solution, which will result in more flowers, brighter colors and a longer flowering period.

In winter, attention should be paid to cold protection. Room temperature must not be lower than 12°C, and it is best at 15-18°C during the day and above 10°C at night. If the temperature is too low, the leaves will turn red, and the flowering period will be delayed or the plant will fail to bloom normally, affecting holiday display.

Although kalanchoe is a perennial plant, root rot of old roots can occur when it has been cultivated for more than 2 years. To make kalanchoe branches more robust, it is recommended to take cuttings and divide the pots every 1-2 years.

Kalanchoe has phototropism, so during the growth period attention should be paid to changing the direction of the flowerpot and adjusting the light so that the plant receives light evenly and the branches grow symmetrically in all directions. After flowering, remove spent flowers promptly to avoid consuming nutrients and affecting the number of flowers in the next bloom. Generally, repot once each spring after flowering. The potting soil should be mixed with 4 parts humus soil, 4 parts garden soil, 2 parts river sand, plus a small amount of bone meal. This growing medium is loose and fertile, has good drainage, and is slightly acidic, which is beneficial to the growth and development of kalanchoe.

Kalanchoe propagation methods

1. Cutting propagation

Kalanchoe is best propagated in May-June or September-October. Select slightly mature fleshy stems, cut 5-6 cm lengths, insert them into a sand bed, water and cover with plastic film. At a room temperature of 15-20°C, they root 15-18 days after insertion and can be potted after 30 days. Commonly use 10 cm pots. If there are not many seedlings, leaf cuttings can be used. Cut healthy, plump leaves from the leaf stalk. After the cut surface dries slightly, insert them obliquely or lay them flat on a sand bed, maintaining humidity. After about 10-15 days, they can root from the leaf base and grow new plants.

2. Cutting method

Kalanchoe blooms from winter to the following spring, so generally it is better to propagate kalanchoe by cuttings in summer or autumn. Because kalanchoe originates from Africa and likes a warm climate with sufficient sunlight, carrying out cutting propagation in summer and autumn can ensure the temperature needed for kalanchoe seedlings to root and survive. Generally, during the seedling growth period, sufficient sunlight must be ensured every day.

Then select a vigorously growing and healthy branch of kalanchoe as the new mother plant, and place it in sandy soil for cultivation. Kalanchoe is not very strict about soil; it is suitable for growing in sandy loam. During cutting propagation, the soil should be loosened to increase soil fertility and provide appropriate drainage, making it more suitable for the new kalanchoe plant to root, sprout and grow.

When the new cutting is placed in sandy loam for cultivation, the amount of water and fertilizer needed for kalanchoe growth must be ensured. Kalanchoe's hometown is Africa, so it is a plant with low water requirements. It is relatively drought-tolerant, so during kalanchoe propagation do not water too much, to avoid accumulation at the roots and the occurrence of root rot. In terms of fertilizer, however, in the early stage of kalanchoe, more additional fertilizer should still be applied to ensure sufficient nutrients during its growth period and to supply the new branches for producing more flowers during the later flowering period.

Precautions

1) Use clean yellow sand, sandy loam or nutrient soil as the medium, preferably disinfected with a 0.1% potassium permanganate solution.

2) Pinch off a 6-10 cm long branch section, which must include two or more leaf base segments. When inserting the cutting, try to cut the cuttings to a uniform height. The lower end of the cut is generally slanted, preferably about 2 mm from the lowest bud eye, which is beneficial for rooting. The upper cut should be flat and at least 4 mm from the uppermost bud, to avoid the upper cut drying out and discoloring after water loss, causing cutting failure.

3) Insert directly into the medium; a depth of 1/2 to 2/3 is better. Firm it down and water thoroughly once. After that, just keep the medium moist. Be careful not to water too much or mist too heavily, as this can easily cause the succulent leaves and stems to rot.

4) After cuttings are taken, if conditions allow, they can be covered with plastic film to keep warm and retain moisture, which can promote rapid rooting of the stems and ensure the survival rate.

5) Freshly taken cuttings should avoid strong light; scattered light conditions are best. Do not fertilize the cuttings right after planting.

6) They root as soon as they are inserted, taking about one week to root. Once new axillary buds and leaves have grown, they can be transplanted.

3. Tissue culture propagation

In the United States and France, from the late 1970s, the stem tips, leaves, stems, flower buds and flowers of Kalanchoe blossfeldiana were used as explants, with MS medium plus 2 mg/L kinetin and 0.1 mg/L naphthaleneacetic acid to induce adventitious buds. Then 1/2 MS medium plus 1 mg/L indolebutyric acid was used to induce rooting. At room temperature of 25-27°C and 16 hours of light, small plantlets can grow in 4-6 weeks.