Red Spider Mites, or Two Spotted Spider Mites, (tetranychus urticae), are garden pests that affect a variety of plants including orchids. Spider mites are "arachnids", related to spiders but smaller and have only one body section unlike the real spiders who have two. There are two varieties, the European red spider mite and the Southern red spider mite.

Because it is a tiny crawling and wingless insect it is difficult to notice and a magnifying glass helps. Mites are recognizable as small "dots" on the underside of leaves, dots that when closely observed are moving. The juveniles have 6 legs and can start laying eggs after 3 days. Adults have 8 legs.

Some consider the "Red Spider mite" and the "Two-spotted spider mite" as being the same. The female red-spider mites turn red and hibernate. Early spring start life as dark red. The "Two-spotted Spider Mite" is partially red and it is called "two-spotted" because of the two very dark, almost black spots on its backside.

The females will lay a half dozen eggs every day in small groups, on the underside of the leaf. The time it takes for the eggs to hatch depends upon the temperature. Juveniles will eat away, sucking the juice out of the plant, living a visible yellowish mark behind. Some spider webbing may also be visible.

The main way of transport of the spider mites are other larger insects and wind. Cooler temperatures slow down the reproductive rate and warm conditions speeds up the life cycle.

Spider mites have many natural predators from lacewings to ladybugs, to other predatory mites. Vegetable oil or soap-based pesticides also work well