Managing Chinese Cabbage in Hoop Houses: Temperature, Water, Fertilizer, and Pest and Disease Control

Hoop-house Chinese cabbage refers to napa cabbage (Chinese cabbage) grown under plastic hoop-house cover. The film retains and raises heat, making it possible to extend the growing period in early spring or late autumn, reduce low-temperature freeze damage, and achieve an earlier market date or a later harvest. Compared with open-field planting, the temperature and humidity inside a hoop house are easier to regulate, the cabbage grows faster, and head formation is more consistent.

Temperature management is the key part of hoop-house cabbage care. At sowing or transplanting, focus on keeping warm to promote seedling recovery and vigorous growth; after the rosette and heading stages begin, if daytime house temperatures get too high, ventilate promptly to prevent disease or leaf overgrowth caused by high heat and humidity. Ventilation should be increased gradually from small to large to avoid cold drafts directly hitting the plants and causing seedling shock; when nighttime temperatures are low, add extra insulation to prevent freeze injury.

For water and fertilizer management, cabbage likes water and nutrients, but evaporation inside a hoop house is slower, so watering should be light and gentle rather than flooding, which can make humidity too high inside. Topdressing should be mainly nitrogen fertilizer combined with phosphorus and potassium fertilizer, applied once each at the rosette stage and the heading stage to help fill out the heads. During heading, keep moisture supply even; alternating dry and wet conditions can easily cause head splitting or tipburn.

Pest and disease control should not be overlooked either. When humidity inside the house is high, downy mildew and soft rot are more likely, so strengthen ventilation to reduce humidity and remove diseased plants and old leaves promptly; for insect pests, focus on cabbage caterpillars and aphids. If heads fail to form, it is often related to excessively high temperatures, insufficient water and fertilizer, or an improper sowing date, and can be adjusted by ventilating to cool the house and topdressing reasonably. Overall, by controlling temperature, controlling humidity, and keeping fertilizer steady, the yield and quality of hoop-house cabbage can be assured.