Clover Mites

Occasionally we get calls about tiny red spiders invading a home, and they almost always turn out to be clover mites. With their bright red to brown color, it's easy to see why these tiny mites can cause alarm for those who aren't familiar with them.

People often ask, "When I squish it, there's a bloody spot. Is it a bedbug?" "Does it bite?" "Will it infest my food?" "Can it damage my home?"

The answer to all of these questions is no. The only damage clover mites cause is from being squished, as the red pigments in their bodies can stain some wall paints.

Clover mites, as their name suggests, feed on the sap of clover but will also munch on grass and many other plants. They don't typically damage plants, except cosmetically, and only when their populations are extremely high. Historically, these mites weren't much of a pest in homes, but the introduction of lawns, succulent landscape plants, and the use of fertilizer has made them more common.

Adults usually lay eggs on tree bark and in other protected crevices, including foundations and siding. Eggs laid in the fall will overwinter and hatch in the spring. Eggs laid in late spring will remain dormant through the summer heat and hatch into nymphs (immature mites) in the fall. Nymphs seek shelter to survive the winter and may enter walls in large numbers. As spring arrives, more mites may be seen indoors as fall eggs hatch and nymphs and adults try to find their way out of buildings.

If these mites get into your house, resist the urge to mash them with your finger. Also, avoid spraying them with pesticides inside your home. If they don't get outside, these mites usually die in a few days. A vacuum cleaner with a brush attachment can usually dislodge them without mashing them into a spot on the wall.

Allowing grass to grow against the foundation supports populations close to the building, and densely planted flowers can do the same. Maintaining a one to three-foot zone of rock along the foundation, devoid of vegetation, will reduce access to the building. 

Keeping your lawn in "golf course" condition with fertilizer and regular watering can spark a population boom, so be careful not to over-fertilize.

As a last resort, a professional application of pesticide to a band of soil adjacent to the foundation 

and extending up the foundation can help suppress activity but large-scale application to the yard is not recommended.