How To Safely Use Insecticide On My Blueberry Bushes?
Q: We have blueberry bushes with lots of holes in the leaves. I’ve used systemic insecticide granules on other plants but since we eat the blueberries, I’m assuming I should not use this product but use something like organic spinosad instead?
A: You are right, systemic insecticide granules are not labeled for use on edible plants. Since some foliage-damaging beetles feed at night, spray the blueberries at dusk, making sure the spinosad hits the underside of leaves. Repeat every four weeks.