What do you spay plum trees with for worms?

To protect plum trees from worms, particularly the plum curculio and other pests, you can use insecticides containing active ingredients like spinosad or pyrethrin. It's advisable to apply these treatments during the early stages of pest activity, typically in spring when the flowers are blooming. Additionally, organic options such as neem oil can also be effective. Always follow the manufacturer's instructions for application rates and safety precautions.