Answer: It's difficult to diagnose a problem without seeing it so I can only offer some general care guidelines. Hydrangeas grow and flower best with about 4 hours of morning sun, but shade from hot afternoon sunshine. They like rich, moist soil so regular watering is a must. Hot, dry winds can dessicate the foliage, as can chemical sprays, especially if the residues remain on the leaves in the summer sunshine. Sevin is a powerful insecticide so I'd only use it if absolutely necessary. You can try pruning your hydrangea back to remove the dead and dying leaves and to promote healthy new growth. Hydrangeas flower on new growth which develops on old growth so when you prune yours back each spring, be sure to prune it back carefully so there is old wood left on which new growth can emerge. Each new stem that grows from the old wood should produce a flower. Hope this information is helpful.
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