The best times to spray apple trees are during the dormant season (late winter to early spring before bud break), right after petal fall (when most petals have dropped), and then periodically every 7 to 14 days throughout the growing season until just prior to harvest. Spraying during bloom should generally be avoided to protect pollinators. Dormant spraying targets overwintering pests and diseases, while post-bloom spraying focuses on preventing insect pests like coddling moth and apple maggot, and diseases such as apple scab. Multiple applications during the growing season are usually necessary for effective control.
