Use bypass pruners to shape perennials that bloom in a single flush, such as false indigo, lavender and cushion spurge.
Cut foliage back by about a third, creating a shape that blends in with later maturing plants in your garden.
Using bypass pruners, cut plants prone to legginess all the way back to the ground after they bloom. Hardy geraniums, Japanese anemone and black-eyed Susan all lend themselves well to this treatment.
Add fresh mulch after shearing and keep plants well watered.
Watch for new growth within a week and, in about two weeks, compact mounds of foliage, sometimes followed by a second flush of bloom.