Look closely and if you find little webs under the leaves or where the leaves meet the stem, or if the underside of the leaves looks dusty, your plant has Spider Mites. On Phalaenopsis the leaves develop tiny pits and look thin. Dendrobium leaves take on a silvery sheen.
Cousins to the ordinary spider, Spider Mites live for about a month. The love hot, dry conditions. At 60 degrees, one female will produce about 20 eggs. Increase the temperature to 80 degrees and her production can reach 13 million eggs! This explains why a plant that looked clean and healthy a week ago is suddenly covered with mites.
Spider Mites are contagious. Adult mites are always looking for other plants. They travel on pets, hands, clothes, and even air currents.
Spider Mites love hot, dry air. Keeping humidity high and temperatures low is the best preventitve control. Where practical, give your plants a shower every couple of months with soapy water.
Although persistent, spider mites are relatively easy to eradicate. They don't have the protective shields which makes controling them somewhat easier than other insects.
Neem Oil is an effective control for spider mites. Mix 1 TBLS of Neem Oil in 1 quart of water in sprayer. Add a drop of dish soap to help the Neem Oil mix with water. Shake thoroughly.
Note: Neem is effective for only 12 hours after mixing.
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