spray fruit trees/bushes
Dormant oils are applied before bud break in the spring. Delayed dormant sprays are applied after bud break before the buds really unfold. These sprays are applied to control insect and mite pests that over winter on the plant as eggs and the oil suffocates the eggs and for scale insects. Oil is use a lot in apples but only in blueberries if you have a scale problem.
Oils are not compatible with sulfur or the fungicide captan which is often used in both apples and blueberries. for this reason horticultural oils are seldom used of insect control in the summer.
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