Mites on Grapevines
Grapevine bud mites are tiny, about 1/10th of a millimeter long, to be exact. Their size, coupled with their clear to white coloring, makes them impossible to see with the naked eye. You can spot them with a microscope, but the more common and much easier method is to wait for telltale signs of damage. The presence of grapevine bud mites can result in buds that are blackened, covered in white fuzz, and/or have a bubbly, rippled appearance to the surface. It can also lead to stunted, misshapen, or dead buds on your grapevine plants. The best time to detect the presence of bud mites is in the spring, before or after bud burst.
Controlling Grape Bud Mites
You can find bud mites on grapevines all year long – a population will go through many generations during the growing season, but the adults born in the autumn will overwinter inside the plant. One method of grapevine bud mite control is releasing beneficial mites that feed on bad ones. Of course, make sure that this new species of mite is amenable to your local environment before you go anywhere near it. Another popular means of controlling grape bud mites is to spray large amounts of sulfur on the vines to kill off the mite populations. Spray during the budding period when the temperature is at least 60 F. (15 C.). Spray again one week later.
