Control Methods for Common Pests and Diseases of Rose Mallow
Rose mallow, also known as marsh mallow or hibiscus mallow, is deeply loved by garden enthusiasts because of its vivid colors, very large flower corollas, long flowering period and strong adaptability, and it is also an excellent material for landscaping. However, rose mallow is also threatened by pests and diseases. Let me tell you about the prevention and control of pests and diseases of rose mallow, and friends who like it can learn about it together.
Rose mallow
The common disease of rose mallow is leaf spot, which is a frequently occurring and common disease of rose mallow and generally harms the leaves of the plant. This disease is caused by infection with fungi of the class Deuteromycetes. The high-temperature and high-humidity period in summer is the peak period of onset. In the early stage of the disease, light black spots appear on the leaf surface. As the disease develops, the spots gradually expand into patches, eventually joining together into sheets, and the leaves curl and then fall off. For the prevention and control of this disease, first, attention should be paid to nutritional balance, and nitrogen fertilizer should not be applied excessively; second, attention should be paid to the ventilation and light transmission of the plant, and overly dense branches should be pruned in time; third, if the disease occurs, spray with a 1000-fold dilution of 75% thiophanate-methyl wettable powder, once every seven days, and spraying two to three times continuously can effectively control the disease.
The common pest of rose mallow is the scarab beetle. If it occurs, first, control the white grubs by using 250 ml of 50% phoxim emulsifiable concentrate, adding 2.5 kg of water, and spraying it around the plant; second, use insecticidal lamps to trap and kill adults; third, use Metarhizium anisopliae to infect and kill the larvae.
Pest and Disease Control Methods for Rose Mallow
Rose mallow, also known as marsh mallow or hibiscus mallow, is a perennial herbaceous flower of the genus Hibiscus in the Malvaceae family. It is native to North America and is widely cultivated in Beijing and areas to the south in China.
Rose mallow is a perennial herb, appearing as a deciduous shrub, with a plant height of 1—2m. The stems are thick, clustered, slanting outward, smooth and covered with white powder. The leaves are alternate, 8~22cm long, with gray stellate hairs on the leaf underside and petiole, and the leaf shape is variable. The base is rounded, and the margin has comb-like teeth. The flowers are large, 28cm in diameter, solitary in the leaf axils, in colors such as pink, red, purple and white, with a flowering period from mid-June to late September.
Rose mallow likes sunlight and does not tolerate shade. It likes a warm and humid climate, fears drought, is relatively tolerant of waterlogging, and grows most luxuriantly in deep, fertile, well-aerated fertile sandy loam. It is tolerant of mildly saline-alkali soil.
Pest and disease control:
The common disease of rose mallow is leaf spot, which is a frequently occurring and common disease of rose mallow and generally harms the leaves of the plant. This disease is caused by infection with fungi of the class Deuteromycetes. The high-temperature and high-humidity period in summer is the peak period of onset. In the early stage of the disease, light black spots appear on the leaf surface. As the disease develops, the spots gradually expand into patches, eventually joining together into sheets, and the leaves curl and then fall off. For the prevention and control of this disease, first, attention should be paid to nutritional balance, and nitrogen fertilizer should not be applied excessively; second, attention should be paid to the ventilation and light transmission of the plant, and overly dense branches should be pruned in time; third, if the disease occurs, spray with a 1000-fold dilution of 75% thiophanate-methyl wettable powder, once every seven days, and spraying two to three times continuously can effectively control the disease.
The common pest of rose mallow is the scarab beetle. If it occurs, first, control the white grubs by using 250 ml of 50% phoxim emulsifiable concentrate, adding 2.5 kg of water, and spraying it around the plant; second, use insecticidal lamps to trap and kill adults; third, use Metarhizium anisopliae to infect and kill the larvae.
Cultivation and Management of Rose Mallow
Reported by Deng Yunchuan, special correspondent of China Landscape Web, rose mallow, also known as marsh mallow or hibiscus mallow, is a perennial herbaceous flower of the genus Hibiscus in the Malvaceae family. It is native to North America and is widely cultivated in Beijing and areas to the south in China. Rose mallow has vivid flower colors, huge flowers, a long flowering period, and tolerates extensive management, making it an excellent material for landscaping. It is often used in flower borders, can also be planted in large patches for ornamental viewing, can be dotted on lawns, or planted at the corners of garden paths. Its cultivation techniques are introduced as follows:
I. Morphological Characteristics and Ecological Habits
Rose mallow is a perennial herb, appearing as a deciduous shrub, with a plant height of 1—2m. The stems are thick, clustered, slanting outward, smooth and covered with white powder. The leaves are alternate, 8~22cm long, with gray stellate hairs on the leaf underside and petiole, and the leaf shape is variable. The base is rounded, and the margin has comb-like teeth. The flowers are large, 28cm in diameter, solitary in the leaf axils, in colors such as pink, red, purple and white, with a flowering period from mid-June to late September.
Rose mallow likes sunlight and does not tolerate shade. It likes a warm and humid climate, fears drought, is relatively tolerant of waterlogging, and grows most luxuriantly in deep, fertile, well-aerated fertile sandy loam. It is tolerant of mildly saline-alkali soil.
II. Planting and Water and Fertilizer Management
Rose mallow can be planted in early spring or late autumn. When planting, decomposed and fermented cow or horse manure or dried chicken manure should be applied as base fertilizer, and the base fertilizer must be thoroughly mixed with the planting soil. Spring planting should be done relatively shallowly, while late autumn planting should be done relatively deeply, and after planting, soil should also be mounded for cold protection and insulation. After spring planting, water immediately for the first watering, water the second time after five days, and water the third time after another week, and thereafter water thoroughly once a month. For seedlings planted in late autumn, after watering thoroughly once, soil can be mounded for insulation. In summer rainy days, accumulated water should be drained in time. Rose mallow likes fertilizer. After applying base fertilizer at planting, (for seedlings planted in spring) a small amount of nitrogen-phosphorus-potassium compound fertilizer can be applied in early April. In late autumn, combined with watering frozen water, apply a shallow application of leaf mold fertilizer once.
III. Pruning
The natural crown shape of rose mallow is relatively loose. During maintenance, it can be pruned according to garden needs. First, attention should be paid not to affect pedestrians; second, overly long branches should be cut back to prevent them from affecting the crown shape; third, after flowering, if seeds are not to be kept, the spent flowers should be cut off in time to prevent excessive consumption of nutrients; fourth, overly dense branches should be pruned to keep the plant ventilated and exposed to light; fifth, before winter, the aboveground branches and stems should be cut off to facilitate mounding soil for cold protection.
IV. Pest and Disease Control
The common disease of rose mallow is leaf spot, which is a frequently occurring and common disease of rose mallow and generally harms the leaves of the plant. This disease is caused by infection with fungi of the class Deuteromycetes. The high-temperature and high-humidity period in summer is the peak period of onset. In the early stage of the disease, light black spots appear on the leaf surface. As the disease develops, the spots gradually expand into patches, eventually joining together into sheets, and the leaves curl and then fall off. For the prevention and control of this disease, first, attention should be paid to nutritional balance, and nitrogen fertilizer should not be applied excessively; second, attention should be paid to the ventilation and light transmission of the plant, and overly dense branches should be pruned in time; third, if the disease occurs, spray with a 1000-fold dilution of 75% thiophanate-methyl wettable powder, once every seven days, and spraying two to three times continuously can effectively control the disease.
The common pest of rose mallow is the scarab beetle. If it occurs, first, control the white grubs by using 250 ml of 50% phoxim emulsifiable concentrate, adding 2.5 kg of water, and spraying it around the plant; second, use insecticidal lamps to trap and kill adults; third, use Metarhizium anisopliae to infect and kill the larvae.