How to Grow China Aster? A Detailed Guide to the Latest Planting Methods

The China aster is also known as Jiangxi la, July chrysanthemum, Gesang flower, etc. It is an annual or biennial herb of the genus Callistephus in the Asteraceae family, produced in Jilin, Liaoning, Hebei, Shanxi, Shandong, Yunnan, Sichuan and other places, growing on hillsides, in grass clumps, by water or in shady sparse woods, and is usually introduced as an ornamental planting for botanical gardens, gardens, courtyards and other public places. Now let us take a look at how to grow China asters!

Growth Habits of the China Aster

The China aster is a shallow-rooted plant, so pay attention to water supply in dry seasons. The plant is robust and not particular about soil, but it does like fertilizer and grows best in fertile sandy soil. It likes sunlight and moisture but is not tolerant of waterlogging, and is susceptible to pests and diseases under high temperature and high humidity. Both its heat tolerance and cold tolerance are relatively poor. Tall varieties are more adaptable and can be planted almost anywhere, while medium and short varieties are less adaptable and require careful management. It should not be grown continuously on the same land, and needs to be planted once every 3 to 4 years. For potted plants, it is best to change the soil once a year.

Propagation Methods of the China Aster

1. China asters are all propagated from seed, and drilling is likely to produce seedlings. Under conditions of 14 to 16°C, they germinate in 4 days and emerge in about 10 days. They are generally sown in spring, but can also be sown in summer and autumn; they bloom 2 to 3 months after sowing, and sowing can be done in batches according to need to control the flowering period.

2. For dwarf China aster varieties, sowing in a greenhouse in February to March, or sowing in a cold frame in March, will bring flowers in May to June; sowing in the open field in April to May will bring flowers in July to August; sowing in early July can bring flowers on “National Day”; when sown in early to mid-August, the seedlings overwinter in a cold frame and bloom the following year on “May Day”.

3. Medium China aster varieties sown in May to June bloom in August to September; when sown in August, they need to overwinter in a cold frame and bloom in May to June the following year. Tall varieties can be sown in both spring and summer, and all bloom in autumn.

Planting Methods of the China Aster

1. During the seedling stage, transplanting China asters 2 to 3 times can make the stems thick and solid, the plant shape full, and the fibrous roots dense, improving drought resistance, waterlogging resistance and lodging resistance. When spring-sown seedlings grow to 5 to 10 cm tall, they can be transplanted at about one month after sowing, and planted in place at about two months after sowing. During the seedling-raising period, water 2 to 3 times and loosen the soil once. After planting in place, water 2 to 3 times, then loosen the soil, and loosen the soil again after rain. Generally, topdressing and watering are carried out after planting in place and before flowering.

2. When growing China asters, pay attention to intertillage and soil moisture conservation, so as to avoid excessive watering or excessive rain making the soil too wet, causing the plants to grow excessively, lodge or develop diseases. After flower buds appear at the branch tips, watering should be reduced to inhibit elongation of the main branches and promote the growth of side branches. When the side branches grow to 2 to 3 cm, slightly increase the water again to make the plant shape full. Topdressing should mainly be phosphorus and potassium fertilizers. Do not grow continuously on the same land, and it is also not suitable to sow or plant seedlings in plots where other Asteraceae plants have been grown, in order to ensure healthy growth.

Pest and Disease Control of the China Aster

1. Yellowing disease: The best control method is to grow the plants in a net house. You can also spray 50% malathion 1000-fold solution or diazinon and other insecticides to control leafhoppers. At the same time, frequently clear the wild weeds around the China asters to reduce sources of infection. In the early stage of the disease, spray medical tetracycline or oxytetracycline 4000-fold solution.

2. Gray mold: Gray mold is caused by Botrytis fungus, whose sclerotia overwinter on diseased residues or in the soil. This disease easily occurs when the temperature is around 20°C and the humidity is very high. Plastic greenhouses suffer more severe disease than glass greenhouses, so pay attention to greenhouse ventilation, reduce humidity, and avoid inappropriate watering. Promptly remove diseased plants and leaves to reduce sources of infection. During the disease period, spray 50% procymidone wettable powder 1500-fold solution or 50% iprodione 1500-fold solution.

3. Fusarium wilt: In the early stage of the disease or before the disease occurs, apply chemicals by root drenching or spraying. Use 50% carbendazim wettable powder 500-fold, pouring 0.25 kg per plant, once every 5 to 7 days, for 2 to 3 consecutive times. You can also use 40% carbendazim suspension concentrate 400-fold solution, or 50% thiophanate-methyl wettable powder 400-fold solution, or 10% shuangxiaoling aqueous solution 200 to 300-fold, or 25.9% kangkuning 500-fold solution. Root drenching with potassium permanganate 800 to 1500-fold solution is also possible.

3. Rust: When pine plants, the alternate hosts, are present near China asters, this disease is likely to occur and spread. Chlorotic spots appear on the upper surface of the leaves, and correspondingly on the underside round pale yellow powdery spore masses can be seen. In the early stage of the disease, spray 15% triadimefon (fenxiuning) wettable powder 1500-fold solution or 12.5% subaoli 3000-fold.

4. Brown spot: Choose well-drained sites for planting, keep planting density appropriate, select disease-resistant varieties, immediately remove diseased leaves when found, and in late autumn collect diseased fallen leaves and diseased residues for centralized destruction. Spray 50% carbendazim wettable powder 1000-fold solution, or 80% zineb wettable powder 500 to 700-fold solution, or 1% Bordeaux mixture, or 755 chlorothalonil 500-fold solution for control, spraying once every 7 to 10 days.