A complete cleanup between crops is also recommended. The effective use of biological control is possible and encouraged. The use of yellow sticky traps helps keep adult whiteflies and aphids in check and monitors their movement and development in concert with the use of Encarsia formosa against the whitefly, Phytoseilus persimilis against the spider mite and Diglyphus isaea against leafminers. The introduction of lady beetles, lacewings or midges for aphids, the use of plastic as a ground cover for thrips and the use of Bacillus thuringiensis for worms offers additional tactics in the battle against bugs in the greenhouse. Regular and frequent inspections of plants for pests and beneficials and good record keeping are essential to pest management.
Environmental management can also influence pest development in the greenhouse.
Temperatures above 85 degrees F and below 60 degrees F slows the development of pests and gives parasites an advantage. High and low relative humidity also slows the development of certain pests. Likewise, the misting of foliage during the day will dislodge aphids, leafminer adults and adult whiteflies. The timely use of ventilation fans or the constant use of circulating fans and the use of airblast sprays also discourages the settlement of adult whiteflies and leafminer adults in the tops of plants. Obviously, extreme high or low temperatures between crops will kill certain pests stages.