There are many species of spider mites with the ability to damage houseplants and gardens. The most common species are the two-spotted spider mite and the spruce spider mite. These mites can lay up to 200 eggs in 10 days. An egg develops into a mature adult in five days, so a mite population can quickly get out of control. Ridding one's house of mites can be both simple and harmless to plants.
Wilt-Pruf is a chemical available at most garden supply stores. Originally manufactured to be used during times of drought, it covers plant leaves with a light film to slow water evaporation. This is harmless to the plant when used as directed. Since spider mites depend on evaporation to survive, spraying the mites three to five times a day with Wilt-Pruf will cause them to die. However, it does not kill the eggs so diligence is essential to keep the mites away.
UltraFine is a highly refined petroleum oil spray that will kill both the mites and their eggs. Spray it on the top and bottom of the leaves, but use caution on soft-leaved plants as it can damage the foilage. Repeat the application in 10 days or so in case you missed eggs or mites on the first application.
Rose Defense II Spray uses neem oil, an extract from the neem seed, and it acts as a natural insecticide, fungicide and miticide. Rose Defense II Spray smothers mites yet is gentle on plants. It is best applied every seven days to kill all mites and then once a month to keep them from returning.
A stream of cold water from a hose or watering will not only knock mites from the plants, it may kill some of them. This is mostly a temporary means of removal as the surviving mites will try to return to the plant once the water is gone. Another reported effective anti-mite remedy is to spray the entire plant with ice water each day for one week. In fact, before pesticides were readily available, these cold water treatments were the primary means of mite control.
Diluting two tablespoons of salt into a gallon of water is an inexpensive and adequate miticide. The solution can be transferred into a spray bottle to use immediately and the excess kept in a garden shed or garage for future use. Spraying plants at dawn or dusk is ideal because evaporation is slower and the solution will be most effective.
Each type of plant, household or garden, does not react the same with different remedies. Check the miticide specifications before applying them to any plant.