This is the perfect time to pinch back certain perennials like tall varieties of Aster, Garden Phlox and Beebalm. Pinching or snipping the plant back by about 1/3 results in a fuller, bushy plant that is self-supporting. It will push the bloom time out a few weeks, so if you're going to try this technique do it before the middle of June. Late bloomers pinched after that may not have time to set bud and flower. For lots more info on manipulating height and bloom time via pinching see Tracy DiSabato-Aust's excellent book The Well Tended Perennial Garden: Planting and Pruning techniques, Timber Press, Portland, OR, 1998.
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