Insect-proof nets act as artificially constructed barriers that keep pests out, thereby achieving the goals of pest and disease prevention and vegetable protection. In addition, the light reflected and refracted by insect-proof nets also has a certain repellent effect on pests.

Insect-proof nets are widely used as barriers to prevent pollen contamination during the production of original seeds and seedlings for vegetables, rapeseed, and other crops. They are also employed after tissue culture detoxification in crops such as potatoes and flowers, as well as in the cultivation of pollution-free vegetables. Additionally, these nets can be used in tobacco seedling raising to protect plants from insects and diseases. Currently, they represent a physical method for controlling pests affecting various agricultural crops and vegetables. By ensuring that consumers can enjoy “safe and reliable vegetables,” these nets make a significant contribution to China’s “vegetable basket” initiative.

The function of insect-proof netting

1. Pest Control: After covering vegetables with insect-proof netting, they are essentially protected from damage by a variety of pests, including cabbage caterpillars, diamondback moths, cabbage armyworms, striped armyworms, yellow flea beetles, leafhoppers, and aphids. According to experiments, the insect-proof netting achieves a control efficacy of 94–97% against cabbage caterpillars, diamondback moths, bean pod borers, and American serpentine leafminers, and a control efficacy of 90% against aphids.

2. Disease Prevention: Viral diseases are devastating pests affecting a wide variety of vegetables, primarily transmitted by insects—especially aphids. Since insect-proof netting blocks this major route of virus transmission, it significantly reduces vegetable infection rates, achieving an efficacy of around 80%.

3. Regulating air temperature, soil temperature, and humidity: Experiments have shown that during the hot months of July and August, under a 25-mesh white insect-proof net, morning and evening temperatures are comparable to those in open fields, while at noon on sunny days, the temperature inside the net is about 1℃ lower than outdoors. In early spring, from March to April, the temperature inside insect-proof-net-covered greenhouses is 1-2℃ higher than outdoors, and the soil temperature at 5 cm depth is 0.5-1℃ higher than outdoors, effectively preventing frost damage. When it rains, insect-proof net houses can reduce the amount of rainfall inside the structure, and on sunny days, they can decrease the rate of evaporation within the house.

4. Shading from intense sunlight: In summer, the intensity of sunlight is high, and strong light can inhibit the vegetative growth of vegetable crops—especially leafy vegetables. Insect-proof nets can provide some shading and protect against direct exposure to intense sunlight. Typically, 20- to 22-mesh silver-gray insect-proof nets have a shading rate of 20% to 25%.

Mesh selection

When purchasing insect-proof netting, pay attention to the mesh size. For vegetable production, a mesh size of 20–32 is ideal, with a width ranging from 1 to 1.8 meters. White or silver-gray insect-proof netting works best. If you want to enhance shading effects, you can opt for black insect-proof netting.

Insect-proof netting is a mesh fabric made from polyethylene, the primary raw material to which chemical additives such as anti-aging and UV-resistant agents have been added. It boasts advantages including high tensile strength, heat resistance, water resistance, corrosion resistance, aging resistance, non-toxicity, odorlessness, and easy disposal of waste. When used properly and stored correctly, it is lightweight and easy to store, with a lifespan of approximately 3 to 5 years.