Hibiscus Cultivation Tips: Propagation Methods and Pest and Disease Control
Hibiscus, also known as Chinese hibiscus, has rich flower colors and many varieties and is a very popular ornamental plant. According to the editor's understanding, this flower is mostly planted in courtyards, but it can actually also be grown in pots. Below is the potted hibiscus propagation and pest and disease control cultivation technique!
Propagation
Cuttage Propagation
Carry it out from March to October, with the highest survival rate during the plum rain season, and carry it out in a greenhouse in winter. Cuttings are best taken from semi-lignified branches of the current year, though stem segments can also be used for cuttage. The cuttings should be 10cm long, with the lower leaves removed and the top leaves retained. The cut should be smooth. Insert them into a sand bed, maintain relatively high air humidity, and keep the temperature at 18°C to 21°C. After insertion, they can be transplanted in 40 to 45 days. If the cuttings are treated with "Root Sun" rooting agent, the rooting period can be shortened.
Treating hibiscus cuttings with "Root Sun" rooting agent has a particularly notable effect. Single-petal varieties can root in about 23 days after insertion, and double-petal varieties can root in about 29 days after insertion, about 16 to 22 days faster than cuttings without any treatment. The seedling stage is short, so there is no need for weeding or fertilizing. Spraying 1 to 2 times with a fungicide and watering 1 to 2 times a day is enough, and the survival rate can reach over 90%, while the survival rate of double-petal varieties is relatively low, at about 40% to 50%. Therefore, double-petal varieties are mostly propagated by grafting, which also gives a high survival rate.
Grafting Propagation Carry it out in spring and autumn. It is mostly used for hibiscus varieties that are difficult to root by cuttage or root slowly, especially double-petal varieties with a low cuttage survival rate. Use branch grafting or bud grafting, with single-petal hibiscus as the rootstock. Grafted seedlings can produce branches and bloom in the same year.
Hibiscus Peony Potted Hibiscus
Potting Management
When the hibiscus root system grows to 3 to 4cm long, it can be transplanted into a pot. Potted hibiscus is commonly planted in pots with a mouth of 15 to 20cm, with 1 plant per pot. Since hibiscus is not strict about environmental requirements, but likes sunlight, hot and dry climates, and is also relatively sensitive to water and fertilizer, cultivation management should be based on its growth characteristics and do a good job with techniques such as watering, fertilizing, pinching and pruning, light, and temperature.
Watering During the growth and flowering seasons, sufficient water must be given to the roots so that the plant can grow vigorously and bloom well. Potted hibiscus should be watered once a day in spring and autumn, and once each in the morning and evening in summer. Sprinkle more water around the placement area to increase air humidity, but never water at noon in midsummer, otherwise the plant will wither. In winter, because the temperature is low, watering must be strictly controlled, otherwise the plant's cold resistance will weaken and it will be prone to freezing damage. In winter, wait until the potting soil is dry before watering. Hibiscus grown in the open ground should also be watered thoroughly only when the soil is dry.
Fertilizing Hibiscus likes fertilizer. During the seedling stage, apply a mixed fertilizer once every 15 days. After flower buds appear, switch to bone meal or chemical fertilizer with a higher phosphorus content. Especially during the flowering and bud-developing period, large amounts of phosphorus and potassium fertilizer are needed. If only nitrogen fertilizer is applied, not only will it fail to bloom, but the branches will grow excessively, making it difficult for flower buds to form, so fertilization must be balanced. After October, fertilization should be gradually reduced, and in winter fertilization should be stopped.
Pinching and Pruning When newly planted seedlings grow to 10 to 15cm tall, promptly pinch off the terminal bud and retain a height of 6 to 8cm. When the newly sprouted branches grow to 6 to 8cm, carry out a second pinching, that is, pinch off the terminal bud. Repeat this several times to form a full crown. Hibiscus has strong sprouting ability and tolerates pruning, so the plant should be pruned once in early spring when the temperature rises, in order to increase the number of branches and achieve abundant flowering. Pruning should focus mainly on shaping, removing weak branches, diseased and pest-infested branches, and slender branches, and cutting back thick strong branches and excessively vigorous branches. In summer, if growth is too fast, prune once every 1 to 2 months.
Temperature The suitable growth temperature for hibiscus is 15°C to 25°C, from March to October it is 18°C to 25°C, and from October to March of the following year it is 13°C to 18°C. In winter the temperature should not be lower than 5°C. If the temperature is below 5°C, the leaves turn yellow and drop, and below 0°C it is prone to freezing damage. Above 35°C, the red hibiscus can still grow normally. Light Hibiscus likes full sun and does not tolerate shade. With sufficient light it grows robustly, has fewer pests and diseases, and produces large, numerous, and brightly colored flowers. Insufficient light easily causes flowers and buds to drop and leaves to turn yellow and fall off. Even if it blooms, the flowers are small, the leaf color is duller, and it is prone to pests and diseases.
Road Greening Effect
Pest and Disease Control Diseases
Common diseases include Phytophthora rot, leaf spot, stem rot, root-knot nematode disease, anthracnose, sooty mold, and flower rot.
① Phytophthora rot. Water-soaked gray lesions appear on the leaves, rapidly enlarge, and develop into dark brown and rotting. If the lesion girdles the stem, the plant soon dies.
Control method: In the early stage of the disease, spray or drench the diseased plants with 500 times diluted zineb solution or 500 to 800 times diluted 25% metalaxyl wettable powder, or spray Bordeaux mixture.
② Leaf spot. In the early stage of infection, pale yellow and red-yellow spots appear on the leaves. After the lesions expand, they become round or oval. In the later stage, the leaves dry up and fall off.
Control method: Use 300 to 600 times diluted 25% carbendazim wettable powder, 1000 times diluted 50% thiophanate-methyl, 500 times diluted 70% maneb, 400 to 600 times diluted 80% mancozeb, 500 times diluted 50% captan, etc., spraying once a week for 2 to 3 consecutive times.
③ Stem rot. This disease mostly occurs in the rainy season and is severe under high-temperature and rainy conditions.
Control method: During the disease period, spray with 800 times diluted 75% chlorothalonil or 600 times diluted 65% zineb. For severely affected nursery land, disinfect the soil with 70% fenaminosulf wettable powder.
④ Root-knot nematode disease. In the early stage of damage, leaf growth weakens and red-brown dead spots appear at the edges. They spread inward, and in the later stage the leaves dry up and fall off.
Control method: Fumigate the soil with undiluted dichlorvos mixture to disinfect it, then sow or transplant two weeks later. You can also bury 15 to 50g of 3% carbofuran granules in the pot for control.
⑤ Anthracnose. It mainly damages leaves, causing them to yellow and fall off, and in severe cases can cause branch tips to die.
Control method: Remove dead branches and diseased leaves and destroy them in a centralized manner or bury them deeply in the soil; strengthen cultivation management and appropriately increase the application of phosphorus and potassium fertilizer to promote robust plant growth and improve disease resistance; at the initial stage of the disease, spray 1:1:200 Bordeaux mixture, or 1000 times diluted 50% carbendazim wettable powder, or 600 to 800 times diluted 75% chlorothalonil wettable powder, once every 10 days. For 2 to 3 consecutive times, the effect is notable.
⑥ Sooty mold. It mainly attacks leaves and branches.
Control method: Promptly control aphids and scale insects. In the early stage of the disease, spray with 1000 times diluted 40% dimethoate, or spray the whole plant with 800 to 1000 times diluted 40% emulsifiable concentrate Supracide.
⑦ Flower rot. The pathogen first invades from the tip of the petals. After onset, the diseased part becomes water-soaked and fades in color. Finally the petals turn brown and rot, and the flower drops.
Control method: In the early stage of the disease, spray 1:1:200 Bordeaux mixture, or 600 times diluted 65% zineb wettable powder, or 600 to 800 times diluted 75% chlorothalonil wettable powder, once every 2 weeks for 2 to 3 consecutive times.
Sooty Mold Pests
Common pests include aphids, scale insects, red spider mites, and slug moths, which use piercing-sucking mouthparts to suck sap on the tender buds, tender branches, and tender leaves of hibiscus, often causing leaves to discolor or even curl.
Control method: Spray with 1500 to 2000 times diluted 10% chulchongjing emulsifiable concentrate, or spray with 0.01% dicofol solution, or spray the whole plant with 800 to 1000 times diluted 40% emulsifiable concentrate Supracide. Once a week for 2 to 3 consecutive times gives a relatively good effect.
Hibiscus is a beautiful ornamental flowering tree, and its planting method is simple and it survives easily. It likes light, and as long as it gets enough sunlight, its flowering period will lengthen. It is one of the best flowers and plants for courtyards, gardens, and other places. All you flower lovers can take a look at its potted propagation methods.
Hibiscus Hibiscus rosa-sinensis Hibiscus Illustrated Guide: How to Grow Hibiscus / How to Propagate Hibiscus
Hibiscus ProfileHibiscus Hibiscus rosa-sinensis
Hibiscus Cultivation Methods and Precautions Introduction to Hibiscus
Hibiscus H. rosa-sinensis, also known as Chinese hibiscus, red hibiscus, Chinese hibiscus peony, elf flower, etc. It is an evergreen large shrub of the Malvaceae family. The stem is upright and much branched, the crown is roughly square, and it can reach 6 m tall. The leaves are alternate, broadly ovate to narrowly ovate, 7-10 cm long, with 3 main veins, the apex acute or acuminate, the leaf margin coarsely serrate or lobed, the base nearly entire, glabrous or with a few sparse hairs on the veins beneath, shaped like mulberry leaves. The flowers are large, with drooping or upright stalks, solitary in the upper leaf axils, and divided into single-petal and double-petal types; single-petal ones are funnel-shaped, usually rose red, while double-petal ones are not funnel-shaped and appear in colors such as red, yellow, pink, and white. The flowering period lasts all year, with the peak in summer and autumn.
Morphological Characteristics of Hibiscus
It is an evergreen large shrub of the Malvaceae family. The stem is upright and much branched, the crown is roughly square, and it can reach 6 m tall. The leaves are alternate, broadly ovate to narrowly ovate, 7-10 cm long, with 3 main veins, the apex acute or acuminate, the leaf margin coarsely serrate or lobed, the base nearly entire, glabrous or with a few sparse hairs on the veins beneath, shaped like mulberry leaves. The flowers are large, with drooping or upright stalks, solitary in the upper leaf axils, and divided into single-petal and double-petal types; single-petal ones are funnel-shaped, usually rose red, while double-petal ones are not funnel-shaped and appear in colors such as red, yellow, pink, and white. The flowering period lasts all year, with the peak in summer and autumn.
Ecological Habits of Hibiscus
It grows in sparse mountain forests, is easy to grow, has strong stress resistance, and has very few pests and diseases. It likes warm, humid climates, does not tolerate cold, and requires sufficient sunlight. It grows well in areas with an average temperature above 10°C. It likes light and does not tolerate shade, and is suitable for slightly acidic soil rich in organic matter with a pH of 6.5-7. In the south it is planted in the ground as a flower hedge, while in areas north of the Yangtze River basin it is grown in pots in greenhouses.
Cultivation Techniques of Hibiscus
For propagation, ring-cut branches and terminal bud cuttings work equally well, but generally 10-12 cm long terminal buds are used. The cuttings can be planted directly into the pots to be sold, generally 2 cuttings per pot. If they are to be sold as small potted plants, the cuttings are inserted into propagation pots (connected trays). Propagate in an enclosed space (such as inside plastic tarpaulin). Rooting begins 35-40 days after cuttage, but this depends on the time of year the cuttings are taken, with a temperature of 22-23°C. The source of cuttings can be obtained from mother plants or from plants to be sold; if obtained from these plants, the cultivation time generally must be extended by another 2-3 weeks. Pot placement space: cuttings should be planted in 11 cm pots using a clay and lime fertilizer medium. Space: place 25-30 pots per square meter. Climate summer temperature: 18+2°C (at sunrise); winter temperature: 16+2°C (at sunrise). Outdoor temperature: 26°C. The temperature of a heated bench can be 2-3°C above air temperature. The minimum temperature refers to use with curtains at night; otherwise the temperature should be raised. Humidity: relative humidity should not be too high. Shading: not needed.
Pest and Disease Control of Hibiscus
The main pests of hibiscus are aphids, mealybugs, cottony cushion scale, and mites (commonly known as red spider mites). These pests are all piercing-sucking pests. That is, they use their mouthparts to pierce into the leaf surface or epidermis of the plant and suck the plant's sap. The leaves of the damaged plant lose their green color, growth weakens, and ornamental value is reduced. After aphids and mites appear, insecticides such as yamansha, yamanjing, and manchongqing can be diluted to a certain multiple and sprayed on the leaves to kill them, once a week, and generally 2-3 times can basically eliminate them. Mealybugs and cottony cushion scale can damage leaves and the epidermis. Generally, imidacloprid-type products or their improved formulations can be diluted to a certain multiple and sprayed on the affected parts to kill them. In severe cases, spray once every 10 days, and 3 times can basically eliminate them.
Medicinal or Dietary Therapeutic Value of Hibiscus
The medical information and health dietary therapy information on Huhua.com is for reference only and cannot be used as a basis for diagnosis or medical treatment. Any health issues should be consulted with professional medical personnel, and the treatment of any disease should follow a doctor's advice.
Ultimate flower-protecting mission: Love yourself, start from reality, and strictly follow a doctor's advice. Toward illness, do not be careless, do not delay, do not give up hope, face it bravely, use love to warm the silent world, and use your heart to care for the flower field within.
The flowers, leaves, stems, and roots of hibiscus can all be used as medicine, mainly the roots. The flowers contain gossypetin, quercitrin, cyanidin glucoside, kaempferol, esters, mucilaginous substances, and vitamins. The leaves and stems contain sitosterol, taraxasterol, acetate esters, and enzymes, etc. The roots contain tannins. Hibiscus flowers are sweet and cold in nature and flavor, and have the effects of clearing the lungs, resolving phlegm, cooling blood, detoxifying, promoting urination, and reducing swelling. They are suitable for conditions such as lung-heat cough, mumps, mastitis, acute conjunctivitis, urinary tract infection, nosebleeds, and irregular menstruation. Hibiscus leaves are mainly used for skin sores. The effects of hibiscus root are the same as those of hibiscus flowers. Chinese hibiscus flowers contain cyanidin sophoroside glucoside, cyanidin diglucoside, and quercetin glucuronide, and have the effect of lowering blood pressure in anesthetized dogs. The Qing dynasty Ben Cao Qiu Yuan says: "There are red and white types; the white one treats white dysentery and white turbidity, and the red one treats red dysentery and red turbidity." Lingnan Cai Yao Lu records: "Clears lung heat, removes phlegm-fire, regulates cough." Lu Chuan Ben Cao: "Cools blood and detoxifies. Treats blood heat, wing blood, blood phlegm, and toxic sores." Nanning Shi Yao Cai Zhi: "Stewing with pig lungs treats coughing blood." In the Ming dynasty, Ben Cao Gang Mu records that Chinese hibiscus leaves or flowers, ground with white hibiscus leaves, burdock leaves, and white honey and applied, can treat carbuncles and mumps. According to Guangzhou Air Force Chang Yong Zhong Cao Yao Shou Ce, Nanning Shi Yao Wu Zhi, and Min Jian Chang Yong Ge Yao Hui Bian, Chinese hibiscus root has the effects of treating irregular menstruation, uterine bleeding, white turbidity, and leukorrhea, as well as relieving cough, reducing inflammation, and treating bronchitis. Chinese hibiscus leaves and stems contain taraxasteryl acetate and a sterol. Ben Cao Gang Mu records that it can "treat carbuncle swelling and mumps." Fujian Min Jian Yao Cao records "resolves heat toxin and reduces carbuncle swelling." Nanning Shi Yao Wu Zhi records "crush and apply to pustules." Lu Chuan Ben Cao records that its medicinal effects are the same as those of Chinese hibiscus flowers. From the above, it can be seen that Chinese hibiscus has been used as medicine in China for at least many years.
Landscape Uses of Hibiscus
The bright and eye-catching flowers of hibiscus open in the morning and wilt in the evening, in brilliant purples and reds. In the south they are mostly scattered along pond banks, in front of pavilions, beside roads, and by walls, while potted hibiscus is suitable for display in living rooms and at entrances.
Cultivation Methods of Hibiscus
Hibiscus is native to China and is distributed in provinces such as Guangdong, Fujian, Guangxi, and Yunnan. It likes a warm, humid, sunny environment, does not tolerate drought, and does not tolerate frost. North of the Yangtze River it must be potted, and in winter it must be moved indoors to overwinter. Hibiscus has a very long flowering period. Under conditions of 15°C to 20°C, it blooms continuously all year. Hibiscus has strong resistance and relatively extensive management, and does not require special care. In maintenance, as long as the following principles are mastered, it can grow robustly.
1. Repotting and pruning For potting soil, loose, fertile sandy loam should be chosen. Before moving it outdoors in early spring each April, it should be repotted.
When repotting, do 3 things: first, replace it with new culture soil;
second, cut off some overly dense and curled fibrous roots;
third, apply sufficient base fertilizer, with a little phosphate fertilizer added at the bottom of the pot. In order to maintain a beautiful tree shape and abundant flowering, and based on hibiscus's strong ability to produce branches and sprouts, pruning and shaping can be carried out around early spring before it is moved out. For each branch, leave 2-3 buds at the base and cut off all the upper part. Pruning can promote new branches, make growth more vigorous, and also make the plant shape more attractive. After pruning, because aboveground consumption is reduced, water and fertilizer should be appropriately moderated.
2. Management after moving out Hibiscus is a sun-loving tree species. In early May it should be moved outdoors to a place with sufficient sunlight. This is also the growing season for hibiscus, so management work such as fertilizing and watering, loosening the soil, and weeding should be strengthened. Apply dilute liquid fertilizer once every 7-10 days. Watering should depend on whether the potting soil is dry or wet; too dry or too wet will both affect flowering. Management after autumn should be careful, and attention should be paid to applying less fertilizer later to avoid producing autumn shoots. Autumn shoots are tender in tissue and weak in cold resistance, and will suffer freezing damage in cold weather. Move indoors in time Hibiscus does not tolerate frost, and must be moved indoors for warmth after Frost's Descent and before the Beginning of Winter. The overwintering temperature should not be lower than 5°C, to avoid freezing damage; and not higher than 15°C, to avoid affecting dormancy. Poor dormancy will make growth and flowering weak the next year. Any furniture room facing south with good insulation conditions can be used for overwintering. When the weather is colder, it can be covered with paper or plastic film for warmth. When first moved indoors, windows should be opened for ventilation every day during the day, and attention should be paid to changes in whether the potting soil is dry or wet, with appropriate watering. On the coldest days, watering has the effect of preventing freezing damage, but fertilizing should be stopped.
Distribution Area of Hibiscus
Native to China, distributed in the provinces and regions of Fujian, Guangdong, Guangxi, Yunnan, and Sichuan.
Propagation Methods of Hibiscus
Cuttage and grafting are commonly used for propagation. Cuttage can be carried out except in winter, but the survival rate is highest during the plum rain season. The best cuttings are one-year-old semi-lignified ones, 10 cm long, with the top leaves retained, the cut smooth, inserted into a sand bed, and rooting occurs about 3 weeks after insertion. Grafting is mostly used for double-petal flower varieties that are difficult to root by cuttage. Either branch grafting or bud grafting can be used, with single-petal hibiscus as the rootstock.
Spring cuttage has a higher survival rate than autumn cuttage, and ground cuttage has a higher survival rate than pot cuttage and also survives faster, generally blooming in the same year. Generally, choose healthy two-year-old branches, though strong semi-lignified branches of the current year can also be used. It is best to cut the middle section of a side branch into cuttings about 15 cm long with 5-7 nodes. The cutting bed soil should use coarse sand or silica with good drainage and strong aeration, disinfected, and then placed into the cutting bed about 15-20 cm thick. The lower leaves of the cuttings should be cut flat with a sharp knife and inserted promptly, to a depth of 1/2. After insertion, immediately water once thoroughly, cover with plastic film, maintain appropriate temperature and humidity, keeping it moist but not wet, with good drainage and aeration, and gradually accept sunlight afterward. Under conditions of maintaining an air temperature of 18-25°C and a relative humidity of 70%-80%, rooting can generally occur after 20 days, and potting can be done after about 1 month.
Cultural Background of Hibiscus
Hibiscus is the state flower of Hawaii. Seeing hibiscus makes people think of beaches with blue seas and blue skies and southern beauties with grass skirts at their waists. It is said that indigenous girls place hibiscus above the left ear to indicate "I hope to have a lover," and above the right ear to indicate "I already have a lover." As for placing it on both sides? Probably "I already have a lover, but I hope to have one more."
Hibiscus looks warm and bold on the outside, yet has a unique flower center. This is formed by many small stamens joined together and wrapping around the outside of the large pistil, and the structure is quite delicate, just like a slender heart beneath a passionate appearance. Red hibiscus is dazzling to the eye and symbolizes burning passion. It is the best decoration for grand festivals and banquets, and also the best flower for celebration flower baskets and flower boards for business openings. Hibiscus flowers are large and gorgeous. Malaysia regards hibiscus as a symbol of living and working in peace and contentment and of prosperity and development. Whether in public places, along both sides of streets, or in home courtyards, hibiscus is used for decoration. Fiji has a traditional folk festival called the "Red Flower Festival," and the red flower here is hibiscus. The "Red Flower Festival" is held in the capital every August and lasts 7 days. People decorate goods with hibiscus flowers, wear colorful formal attire, put on strange and bizarre masks, and parade behind the band. Young girls selected from various places to participate in the "Red Flower Queen" contest ride on decorated floats to fully show their grace. The climax of the festival is selecting three "Red Flower Queens." The box office income from the "Red Flower Queen" selection is donated to charity.
Flower Language of Hibiscus
Flower language: fresh romance, subtle beauty. Hibiscus is the state flower of Hawaii. Seeing hibiscus makes people think of beaches with blue seas and blue skies and southern beauties with grass skirts at their waists. It is said that indigenous girls place hibiscus above the left ear to indicate "I hope to have a lover," and above the right ear to indicate "I already have a lover." As for placing it on both sides? Probably "I already have a lover, but I hope to have one more." Hibiscus looks warm and bold on the outside, yet has a unique flower center. This is formed by many small stamens joined together and wrapping around the outside of the large pistil, and the structure is quite delicate, just like a slender heart beneath a passionate appearance. Red hibiscus is dazzling to the eye and symbolizes burning passion. It is the best decoration for grand festivals and banquets, and also the best flower for celebration flower baskets and flower boards for business openings. Hibiscus flowers are large and gorgeous. Malaysia regards hibiscus as a symbol of living and working in peace and contentment and of prosperity and development. Whether in public places, along both sides of streets, or in home courtyards, hibiscus is used for decoration. Fiji has a traditional folk festival called the "Red Flower Festival," and the red flower here is hibiscus. The "Red Flower Festival" is held in the capital every August and lasts 7 days. People decorate goods with hibiscus flowers, wear colorful formal attire, put on strange and bizarre masks, and parade behind the band. Young girls selected from various places to participate in the "Red Flower Queen" contest ride on decorated floats to fully show their grace. The climax of the festival is selecting three "Red Flower Queens." The box office income from the "Red Flower Queen" selection is donated to charity.
Hibiscus Pictures
How to Control Pests and Diseases in Chinese Hibiscus
Chinese hibiscus, also called hibiscus, is a beautiful ornamental plant. Its flowers are mostly bright red. It mostly grows in the Lingnan area of China and is also an ornamental plant that can be cultivated at home. However, during cultivation, this Chinese hibiscus often suffers from pests and diseases, and attention should usually be paid to prevention. So how should Chinese hibiscus prevent pests and diseases? Below, the editor will explain in detail.
How to Control Pests and Diseases in Chinese Hibiscus1. Control of Chinese Hibiscus Leaf Spot
Chinese hibiscus leaf spot mostly occurs in late autumn when the weather turns cold. After this disease occurs, pale yellow or red-yellow spots appear on its leaves. The lesions slowly expand, and in severe cases black substances appear. The best way to prevent this disease is prevention. When strong winds and cooling occur in autumn, carry out warmth-keeping treatment in time. After the disease occurs, zineb can also be sprayed.
2. Control of Chinese Hibiscus Stem Rot
Stem rot is also a frequently occurring disease during the growth period of Chinese hibiscus. It mostly occurs in the rainy season and is caused by fungi. After onset, the root crown of the plant mostly appears dark brown, the subcutaneous tissue rots, and in severe cases the diseased plant can die. Usually, to prevent this disease, rain should be prevented from washing over the plant, and around the rainy season, thiophanate liquid should be sprayed in time, once every ten days, with a particularly good preventive effect.
3. Control of Chinese Hibiscus Root-knot Nematode
Root-knot nematode is also one of the diseases most likely to appear during the growth period of Chinese hibiscus. After it occurs, red-brown spots appear on the leaf edges of the plant and spread inward, and in severe cases the leaves fall off. This disease is particularly difficult to control. When growing it at home, you can directly change the soil and repot. The new soil must be exposed to the sun for disinfection, and the old soil cannot be used. In addition, some aldicarb granules can be applied into the new soil to prevent this disease from occurring again.