Malathion can aggravate some spider mite problems, despite being advertised frequently as effective for mite control. Water Management Adequate watering of plants during dry conditions can limit the importance of drought stress on spider mite outbreaks. Periodic hosing of plants with a forceful jet of water can physically remove and kill many mites, as well as remove the dust that collects on foliage and interferes with mite predators. Disruption of the webbing also may delay egg laying until new webbing is produced. Sometimes, small changes where mite-susceptible plants are located or how they are watered can greatly influence their susceptibility to spider mite damage.
Few insecticides are effective for spider mites and many even aggravate problems.
Furthermore, strains of spider mites resistant to pesticides frequently develop, making control difficult. Table 1 includes a summary of pesticides that may be useful for managing spider mites. Control of Spider Mites on House Plants Control on house plants can be particularly frustrating. When attempting control, treat all susceptible house plants at the same time. Trim, bag and remove heavily infested leaves and discard severely infested plants.