With careful attention to deadheading, you can keep many perennials looking their best all summer. Deadheading is a simple technique. It is the removal of spent flowers which encourages repeat blooms or to enhance the plant’s general appearance. If you are wondering how deadheading will encourage a plant to produce a second flush of flowers, you need to understand a little about a plant’s biology.

 Let me describe deadheading from the plant’s point of view. The plant’s biology is locked into seed production. If you prevent seed formation by removing the spent flowers, the plant will produce more flowers in order to complete its life cycle. So, when you remove the spent flowers, you trick the plant so it diverts its energy from creating seeds to create more flowers and/or better foliage.

 I use three different methods to deadhead plants. Gardeners long before me coined the terms “snip, shape, and shear” to describe each of the three methods for deadheading.

 Snipping is the most common method of deadheading. It is the removal of individual flowers and/or the flower stalks.  It works best for plants that bloom over a long period of time, rather than all at once.  To deadhead perennials by snipping; make the cut at the junction where the flower stalk ends but just above the first set of leaves. The new flowers will grow from the leaf axils, which is why it is important to cut above those leaves.

Perennials to Snip: Tall Phlox, Salvia, Lupine, Daylily, Iceland Poppies, Columbine, Pin Cushion Flower, Shasta Daisey and Roses

Perennials to Snip to Improve Appearance ( but will not rebloom): Astilbe, Bergenia, Hosta, Peony, Siberian Iris, and Lamb’s Ears

 Shaping is the best method for perennials that bloom all at once such as lavender. The tool that I prefer to use for shaping is a hedge shears. When I shape a plant, I cut it back by one third, removing all of the flower stalks, and some of the leaves.  As I shape a plant, I try to mimic the plant’s natural growth form. Without shaping some perennials like lavender, become leggy, thin, and unattractive. Shaping this summer will create a dense plant with lots of flowers for next summer.

Perennials to Shape: Lavender, Artemisias, Santolina, and Cushion Spurge I tend to shear any plant that gets leggy after blooming just above ground level about 3  to5 inches depending on the variety. Shearing plants to the ground may sound a bit extreme, but it is the best way to treat leggy plants.  It works on plants that are dense and covered with blooms but crumble under the weight of the flowers.  Once you shear back a plant be sure to give your plants extra water and a little fish fertilizer. Within a week you will have new growth and in two weeks a mound of fresh compact foliage. Perennials to Shear: Hardy Geraniums, Lungwort, Brunnera, Baby’s Breathe, Coreopsis, Catmint (Nepeta), Bachelor’s Button, and Jacob’s Ladder

 Not all perennials require deadheading. Many plants have seeds heads that are a source of food for birds and other wildlife during the fall and winter months. In addition, many seed heads are attractive and provide an element of winter interest. Perennials that I recommend that you don’t deadhead are: Japanese Anemone, Blue Mist Spirea, Snakeroot, Rudbeckia, Tall Sedums and Ornamental Grasses.