This spring, keep an eye out for the tiny Psyllobora beetle, one of the many “lady beetles”. This newly researched beneficial insect feeds on powdery mildew and nectar. If you look closely, you can see this 1-2 mm beetle feasting on nectar in the small blossoms of white alyssum. They are cream to beige with black spots.
About 200 “lady beetle” species occur in California and most are predators predominantly as larvae. While adults will also feed on aphids, thrip, mealybug and other soft-bodied pests, their diet is more nectar and pollen based. Don’t mistake the larvae forms as pests! If too much powdery mildew is getting you down, treat affected plants with Bonide Rose Rx or Neem Oil, sesame based Organocide, or Serenade. These sprays are safe to use in organic gardens.