This year, however, it seems spider mite damage has been more intense on junipers, arborvitaes and Cypress than on lantana and azaleas.
I’m guessing they seem so bad this year because most people don’t know how to test for spider mites, and they’re not using proper control measures. That might be due, in part, to many people moving to our region from northern states, where evergreens never experience spider mites. So, they ignore the tell-tale signs until the damage is widespread.
So, the first step is to determine if spider mites are really the problem. Since they are so small, there’s little chance that the average homeowner will see them with the naked eye, so you should perform the “white paper test.” Hold a blank sheet of paper under a leaf cluster where there’s a bit of damage and tap the cluster downward towards the paper. If you’ve got spider mites, a bevy of the tiny critters will fall to the paper and start scampering everywhere.
The best control measure, in my opinion, is a liquid systemic insecticide with acephate as the active ingredient. “Acephate” will be printed in very tiny letters on the product label. I prefer that you stay away from imidacloprid-based systemics, for a couple of reasons. First, acephate provides a bit of contact-kill in addition to a systemic control – imidacloprid does not. Second, research has shown that imidacloprid-based controls are a severe threat the bee population. I agree that all systemic insecticides can adversely affect bees. However, acephate has been around a lot longer than imidacloprid, and talk of bee colony collapse increased after the introduction of imidacloprid. So, play it safe in this instance.
There are also some all-natural or organic products designed to control spider mites. Neem oil is one, and some products like Mite-X from Bonide contain a combination of natural cottonseed, clove and garlic oils. Spinosad has also been known to help control these critters. The downside to using natural products, however, is the need to repeat applications several times to get total control.