When do you apply dormant spray on fruit trees
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Dormant oils are useful for treating the eggs of insects overwintering in the nooks and crannies of your trees. The oil works by smothering the eggs in a coating of oil which prevents them from breathing. The best time to use this product is in the late winter- early spring before buds begin to swell.
It is important that you don’t spray when trees are in bloom, or when freezing temperatures are expected. The optimum temperature is between 4c – 20c. For maximum benefit, don’t spray when rain is expected or if it’s very windy.
Here are two websites that you may find useful.