By Carl Cantaluppi
Watch the weather reports and be prepared to apply dormant sprays to fruit trees. The temperatures should be high enough (at least 40 degrees F.) so the spray material dries before the temperature drops to freezing. Otherwise, plant tissues might be injured.
A dormant oil application on fruit trees and blueberries will help control scale insects. Remember that dormant oil is not a cure-all to control all insects that attack fruit trees. Timely applications of other insecticides throughout the growing season will ensure less insect damaged fruit.
When applying dormant oil, thorough coverage of the limbs, branches, and twigs is very important so that you do not get a re-infestation of insects from the unsprayed area of the tree. Applying the spray during mid to late morning is advised so there is time for the spray to dry before the temperatures drop to
freezing. Try to apply the oil before buds swell; however, you can apply dormant oil on apples up to the fruit bud growth stage of “green tip”.