Key Points of Choy Sum Cultivation Techniques: Management Methods from Sowing to Harvest

Choy sum is a biennial or annual herbaceous vegetable of the genus Brassica in the crucifer family, also known as flowering cabbage, with its tender flowering stems and young leaves as the main edible parts. It prefers a cool and humid climate and can be grown almost year-round in the warm regions of southern China. It is a common leafy green on dinner tables in South China, with a short growth cycle and quick results, making it very suitable for home vegetable gardens and field rotation planting.

Choy sum is generally grown mainly by direct seeding. It is best to choose a loose, fertile plot with good drainage, deep-plow and sun-bake the soil, then apply plenty of decomposed organic fertilizer as a base fertilizer before preparing the land into beds. After the seeds are evenly broadcast, cover them with a thin layer of soil and keep the soil moist; at a suitable temperature they will soon sprout. After emergence, thinning and final spacing should be done in time to avoid overcrowding and leggy growth of the seedlings; leaving a reasonable plant spacing helps the stems grow thick and sturdy.

Choy sum grows quickly and has a relatively high fertilizer demand. Topdressing should follow the principle of light fertilizer applied frequently, mainly with nitrogen fertilizer and appropriately combined with phosphorus and potassium fertilizer, to promote plump and full growth of the stems. For water management, keep the soil alternately dry and wet; replenish water in time during drought, and pay attention to drainage on rainy days to prevent waterlogging that can rot the roots or induce disease.

Common pests and diseases of choy sum include aphids, cabbage caterpillars, and downy mildew. In daily management, patrol the field frequently and apply pesticides in time once insects or disease spots are found. You can also combine this with clearing weeds and diseased leaves and reasonable crop rotation to reduce their occurrence. When the flowering stems reach a certain height and flower buds first appear at the top, they can be harvested. At harvest, leave a few leaves and axillary buds at the base so that side stems can continue to sprout, thereby extending the harvest period and increasing the overall yield.