By Gail Vanik
A long time ago, in another home, I had two dwarf Alberta spruce trees. One year, they didn’t seem to be doing very well, and I eventually noticed fine, spiderlike webs popping up all over them.
Ah ha! My little trees had a bad infestation of spider mites.
Spider mites can infest just about any plant – trees, shrubs, flowers, veggies, herbs and even houseplants, and they are quite common this time of year.
They are extremely small, and the first way you’ll spot them will be on the underside of leaves. The plant may not seem to be doing well, or it may even look just fine, but make a close inspection of the leaves, and you’ll notice a speckled appearance or small brown or yellow dots.
If your infestation is bad enough, you will begin to notice extremely fine spider webs covering your plant as I did. They’re a telltale sign that spider mites are present, and then you know exactly what you’re dealing with, so you’ll know what treatment to apply.
They do their damage when they suck the sap out of the cells of your plant, and the plant dehydrates. The plant will appear to dry out even though you’ve been watering it. Leaves or needles may start to drop. Since they are so small and difficult to see, you can test for them by taking a sheet of white paper and holding it beneath the plant. Tap the plant gently, and the mites will fall onto the paper and look like you sprinkled black pepper on the page – except it will be moving.
Spider mites are just that - spiders. Since they are eight-legged, they are technically in the arachnid family, so they are not insects at all, and traditional “insecticides” won’t always work in treating an infestation.
Some gardeners have tried simply hosing them off with a high-pressure wash, but most of the time, this isn’t terribly effective. Neem oil or Bonide’s Mite X will work to smother them, and can be effective if you are looking for an organic control or if your mites are on edibiles.
Captain Jack’s Dead Bug Brew is effective on outdoor spider mite infestations. This product is also labeled for organic gardening and can be safely used in your vegetable garden. Since mites tend to congregate on the underside of leaves and foliage, once you mix this up, be sure to hit those areas well when you spray.
If you have a severe infestation, you might need a miticide to treat the problem. Bonide’s Systemic Insect Control is a good choice for indoor plants or those you might bring indoors later in the season. It works as both a miticide and insecticide and can be used as a broad spectrum control in case you’re not really certain what’s bugging your plants.
No matter where your mites are hanging out, you’ll want to get them under control as quickly as possible because damage can be severe. If your plant has damage only on a few leaves, chances are it will recover quickly on its own without any special care once the mites are gone. A light application of fertilizer may help give the plant a boost to put it back on the road to good health. However, remember that dwarf Alberta spruce I had long ago? Since it wasn’t in a part of the yard that I frequented or kept a close eye on, the tree eventually had to be removed and destroyed because the mites had damaged it so badly. So, be sure to check monthly and also inspect your plants before moving any of them inside for the winter.
Spider mites thrive in weather that is extremely hot and dry, so they’ve been rampant this summer. While they are annoying and the webs can be ugly, among the pest world, they can be some of the easiest to clean up if you spot them early enough.
Gail Vanik can be reached at 970-565-8274 or by email at fourseasons@animas.net.