What You Need to Know About Spider Mites and Evergreens

Are your shrubs looking sad? Have your plants been drooping or yellowing? If so, we need to talk.

It’s easy to attribute wilting plants to extreme summer temperatures, but there may be another cause: spider mites. These tiny pests can cause big problems for North Texas greenery, and they often mimic the appearance of heat stress. It’s important to know the signs of spider mites and how to manage and treat an infestation.

What Are Spider Mites?

Spider mites are among the most common garden and landscaping pests in Texas. Prevalent in the summer months, these tiny arachnids are no bigger than a pinhead and are usually red, brown, or light tan in color. Spider mites are almost impossible to spot (unless they are clustered together), but they do leave telltale evidence of their presence: small, wispy silk webs on the underside of leaves. One of the simplest ways to determine if you have spider mites is to take a sheet of white notebook paper, place it under several branches and give the branches a good shake; the mites will fall onto the white paper, where they are easily observed.

Locally, spider mites tend to converge on evergreen shrubs, trees, and xeriscape plants. Their favorite trees also happen to be popular in North Texas: Cedar, Oak, Cypress, and Elm are all loved by spider mites.

Small Bug, Big Impact

Because spider mites are tiny, you may not notice their appearance until your plants start to show signs of stress. Early indicators include a stippling appearance on foliage or a gray appearance on leaves. Plants with a spider mite problem lack their usual luster and may also drop their leaves early.

Internally, spider mites do significant damage that may affect a plant for years. They poke tiny holes in a plant’s leaves, then suck nutrients out while also excreting toxins. This not only damages a plant’s exterior defense system; it also stifles the plant’s ability to heal itself. Over time, this damage can become irreparable.

Managing a Mite Infestation

Because spider mites can affect a plant’s health for years, it’s important to address the problem quickly. Arborists are especially well-versed in dealing with these pests and can quickly assess the damage and determine how to best manage an infestation.

Spider mites lie dormant in cooler months, so the best defense is often preventative maintenance. Overwintering plants can be treated with applications that stop spider mites at the early stages of development, significantly lowering the number of mites.

Depending on the severity of an infestation, there are several treatment options. The first and simplest option is to take a garden hose and vigorously hose the plant down and dislodge the mites. For larger or more severe cases, use an insecticidal soap or insecticidal oil, such as Neem oil, to treat the problem. Whichever method you choose, be sure to strictly follow the manufacturer’s recommendations to avoid further injury to the plant or yourself.

With a little know-how, you can keep your evergreens standing and proud year-round. If you suspect you have spider mites on your commercial property, we suggest contacting us to determine a plan of action. The sooner you address the problem, the sooner your plants can regain their health and color.