Specifications and Types of Insect-Proof Nets for Greenhouses

Specifications and types of insect-proof nets for greenhouses are generally indicated by "mesh count".

   "Mesh count" refers to the number of mesh lines within a 1-inch (1 inch = 25.4 mm) length. In addition to the mesh count reflecting the size of the insect-proof net's openings, the opening size also depends on the diameter of the mesh lines. The ventilation area of the insect-proof net can be calculated based on the mesh count and the diameter of the mesh lines. For example, with a mesh line diameter of 0.2 mm and a specification of 64 mesh, the total length of mesh lines per inch is 12.8 mm (64 lines × 0.2 mm), and the total length of the openings is 12.6 mm (25.4 mm - 12.8 mm). There are 63 openings per inch (25.4 mm), each with a width of 0.2 mm and an area of 0.04 mm². Therefore, per square inch of the insect-proof net, there are 63 × 63 openings, with a total opening area of 158.76 mm² (0.04 mm² × 63 × 63). It can be calculated that the ventilation area of this insect-proof net is 24.6% of the total area of the net.

     Currently, there are three main types of insect-proof nets used in production to meet the light requirements of different vegetable varieties and the need to repel pests. The first is silver-gray insect-proof nets or aluminum foil strip insect-proof nets, which are effective in repelling aphids and can reduce the temperature inside the greenhouse. The second is white insect-proof nets, which have better light transmittance than silver-gray ones and are more commonly used, though the temperature inside the greenhouse in summer is slightly higher than in open fields, making them suitable for most light-loving vegetable cultivation. The third is black insect-proof nets, which provide effective shading and cooling.