One method to try involves spraying the plant with a strong jet of water once or twice a day to dislodge some of the insects and to create an environment that is cooler, more humid and less favorable for spider mite reproduction. Several days or even weeks of this treatment will be required to make a noticeable difference in spider mite populations. Horticultural and dormant oils are also useful on plants with a history of spider mite problems. Horticultural oils can be sprayed on landscape plants during the summer, although some leaf discoloration or phytotoxicity may occur on some plants. Make sure your plant is listed on the label before spraying to prevent damaging the plant and follow the label directions for use of the product.
Dormant oil is used during the winter or very early spring prior to bud break.
It is useful in killing overwintering mite eggs and can help suppress mites populations. In cases of very severe infestations, use of a chemical miticide may be necessary.