Peach leaf curl distorts leaves and disfigures fruit. If you neglected to spray on Thanksgiving, do it now and again on Christmas and Valentine's Day. Mix in a sticking agent such as Sta-Stuck with the spray for best results. They need two years to complete their life cycle. The seed germinates and produces foliage the first year, then it flowers, sets seed and dies.
Foxgloves are a popular example.
Here's a guide that can be used from her farm in Pennsylvania to California, giving a great overview of annuals, perennials, vines, shrubs and flowering trees that Americans love. It details virtually all aspects of growing and caring for everything from achillea to wildflowers. Handsomely illustrated and tightly edited, it's a valuable addition to the gardener's bookshelf. Let us hear from you.