Help With Hydrangea

My 4-foot hydrangea hasn't bloomed since I bought it. As instructed, I cut the plant back in fall when the leaves and stem are yellow. What can I do to make it bloom?

—Rae Jacobs, Coventry, Connecticut

Melinda: If you have white-flowering hydrangeas, keep in mind that they bloom in summer on new growth. Therefore, they can be pruned in fall or spring. Although they're one of the few shrubs that flower in shade, heavy shade can reduce or eliminate blooms altogether. The same is true if the plant receives too much nitrogen. Stop fertilizing the plant and see what happens. If it blooms, excessive nitrogen was the culprit. It's a different story if you have a blue- or pink-flowering hydrangea. These varieties produce blooms on old wood, not new growth. Therefore, the plant shouldn't be pruned back in fall. Instead, wait until after it flowers (or should have flowered) in summer.