What does spider mite dislike in a greenhouse? - briefly
Spider mites avoid environments with high relative humidity and wet leaf surfaces, and they are deterred by the presence of predatory mites such as Phytoseiulus persimilis. Maintaining temperatures below 25 °C further reduces their activity.
What does spider mite dislike in a greenhouse? - in detail
Spider mites thrive in dry, warm environments; increasing relative humidity to 60 % or higher creates conditions they avoid. Moist air interferes with their ability to disperse and reduces egg viability.
Temperatures above 30 °C accelerate development, while keeping daytime temperatures around 20–25 °C slows population growth. Cooler nights, especially below 15 °C, further suppress activity.
Introducing natural enemies such as predatory mites (Phytoseiulus persimilis, Neoseiulus californicus) and insects (lady beetles, lacewings) provides biological pressure. Regular releases maintain predator populations that actively hunt spider mites.
Physical disturbance of foliage—gentle shaking, high‑velocity air streams, or water sprays—dislodges mites and disrupts their webbing. Repeated applications prevent re‑establishment.
Using plant varieties with dense trichomes or resistant cultivars reduces suitability for feeding and oviposition. Selecting such species limits colonization.
Applying horticultural oils or soaps at recommended concentrations suffocates mites without damaging plants. These products must be used when leaf surfaces are wet to maximize contact.
Maintaining clean greenhouse hygiene—removing plant debris, disinfecting tools, and sealing entry points—eliminates refuge sites and reduces accidental introductions.
Combining elevated humidity, moderated temperature, biological control agents, mechanical agitation, resistant plant choices, appropriate oil or soap treatments, and strict sanitation creates an environment that spider mites find inhospitable.