Management for greenhouse vegetables in winter

Management measures for greenhouse vegetables in winter due to low temperature and insufficient sunlight
Select stress-resistant varieties and cultivate strong seedlings: In northern facility vegetable production areas, select eggplant and melon varieties that are resistant to low temperature and low light, have strong fruit setting ability, and are disease-resistant. Use biological substrates for seedling cultivation, control water appropriately, and avoid transplanting excessively long or leggy seedlings into the greenhouse.
Strengthen heat preservation and storage to increase soil temperature: Install windbreaks outside the facility and cover the inside with multiple layers, ensuring a distance of at least 10 centimeters between the agricultural film and the vegetables. Spread rice husk ash, wood ash, etc. between the vegetable rows, or cover the ridges and vegetables with straw, rice straw, etc. If available, use heating equipment to increase the temperature.

Supplement with artificial lighting as needed: Install supplemental lighting in the facility, using incandescent bulbs with a power of around 1000W, placing one bulb every 10 meters, and providing supplemental lighting for 4 hours daily. If artificial lighting is unavailable, ensure sufficient light exposure by uncovering and covering the insulation material in the morning and evening. Other methods to increase light exposure include pruning and trellising vines, reducing water droplets on the greenhouse film surface, and hanging reflective film on the north wall of the greenhouse.

Strengthen production management and control water and nitrogen: In cold and low-light weather, appropriately reduce watering and topdressing. If vegetables wilt due to lack of water, choose a sunny day to carry out drip irrigation under film or water lightly, and topdress with fertilizer. Topdressing should mainly consist of compound fertilizer, avoiding excessive application of nitrogen fertilizer. Foliar spraying with appropriate concentrations of brassinolide and other cold resistance inducers can also improve plant resistance.
Timely ventilation and dehumidification are crucial for pest and disease control: In northern greenhouse production, air humidity should be scientifically regulated, with ventilation scheduled for midday on sunny days whenever possible. Diseased, old, and yellow leaves should be removed promptly to improve ventilation and light penetration. In southern regions, low temperatures and insufficient sunlight in winter are often accompanied by high humidity, which easily induces diseases such as gray mold, damping-off, and sclerotinia. Therefore, timely application of low-toxicity, low-residue, broad-spectrum fungicides is essential.