Detailed Explanation of the Key Points of Pollution-Free Vegetable Cultivation Techniques

Pollution-free vegetables are also called clean and hygienic vegetables. Specifically, this means that during the vegetable cultivation process, comprehensive agricultural control measures are mainly adopted, high-residue pesticides are reduced or not used, and microbial pesticides, natural enemies and parasitic insects are used for pest and disease control, so that the content of harmful substances in vegetable products reaches the hygiene standards set by the state. In appearance, they must have the characteristics and traits of the variety, the stems, leaves or fruits must be fresh and tender, with no off-flavor, no yellow leaves or old leaves, no disease spots or insect spots, and a pure flavor.

I. Production Conditions for Pollution-Free Vegetables

Selection of production base: Establishing a pollution-free vegetable production base is the primary condition for pollution-free production and a key measure to prevent harmful substances in the environment from contaminating vegetables. Vegetable plots must be planned in a unified way, far from towns, and must avoid the three wastes as much as possible, with fresh air and no dust or toxic gas pollution. Water sources must be clean and contain no harmful substances; the soil must be loose and clean, free of industrial waste, with matched ditches and channels and guaranteed harvests in both drought and flood. It is strictly forbidden to irrigate with stagnant water or industrial wastewater, and the forest network belts must be complete.

Application of fertilizers: Rational fertilization is required, and soil testing and formulated fertilization should be carried out. Fertilization should be based mainly on organic fertilizers, supplemented by other fertilizers, and multi-element compound fertilizers should be used as much as possible. Before plowing, apply 4000-5000 kg of high-quality barnyard manure, compost or garbage manure per mu, and plow it into the deep part of the plow layer, with shallow-layer fertilization as well; apply 150-200 kg of decomposed cake fertilizer per mu and mix in compound bacteria to suppress the occurrence of pests and diseases. For topdressing, use decomposed human excrement or dried night soil as the main material, supplemented by multi-element compound fertilizers. In the middle and late stages, an appropriate amount of nutrient solution may be used for foliar topdressing to coordinate growth and increase yield.

II. Technical Regulations for Pollution-Free Vegetable Production

Adopt advanced supporting cultivation techniques: During the cultivation process, make full use of conditions such as light, heat, water and air, and through environmental control create environmental conditions that are favorable for vegetable growth and unfavorable for the occurrence of pests and diseases. For example, use techniques such as plastic film mulching, grafting cultivation and soilless cultivation. In greenhouse production, pay attention to strengthening ventilation and light transmission; in winter and spring, prevent low temperature and high humidity, increase light, supplement carbon dioxide gas fertilizer, and apply greenhouse heating and insulation techniques; in hot and rainy seasons, use shade net techniques for cooling.

In addition, select early-maturing, highly resistant and excellent varieties, apply double-film early-maturing cultivation, use nutrient pot seedling raising, develop greenhouse and plastic tunnel production, apply grafting techniques, promote sprinkler irrigation, drip irrigation and moist irrigation, do a good job in the testing and demonstration of nutrient solution and soilless cultivation techniques, and use smoke and dust methods for pest and disease control in greenhouses to reduce temperature and control the occurrence of pests and diseases, so as to achieve the goal of pollution-free vegetable production.