Snipping and Shaping Perennials

With careful attention to deadheading you can keep your perennials looking their best all summer. Deadheading is a simple technique. It is the removal of spent flowers and flower stalks to encourage repeat blooms or to enhance the plant's general appearance. You may wonder how deadheading will encourage a plant to bloom again. If so, it is important to understand a little about a plant's biology.

Let me describe deadheading from the plant's point of view. The plant's entire purpose is to produce seeds for the next generation. If you prevent seed formation by removing the spent flowers, the plant will continue to produce more flowers. The plant needs to complete its life cycle and produce seeds. If you remove the spent flowers, you divert the plants energy from creating seeds toward more flowers and better foliage.

I use three different methods to deadhead plants. Gardeners long before me have 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 or flower stalks. It works best for plants with a few flowers that bloom over a long period of time, rather than all at once. To deadhead perennials by snipping, cut where the flower stalk ends and 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 these leaves

Perennials to Snip for Rebloom: Tall Phlox, Salvia, Lupine, Yarrow, Iceland Poppies, Lady's Mantle, Baby's Breath and Verbena bonariensis.

Perennials to Snip to Improve Appearance: Astilbe, Bergenia, Hosta, Peony, Lambs Ears and Hosta.

Shaping is the best method for perennials that bloom all at once like lavender.

The tool that I prefer to use for shaping is a pair of 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. Many plants like lavender benefit from shaping. Shaping creates a dense plant with lots of flowers.

Perennials to Shape: Lavender, most Artemsias, Sage, Santolina, Blue False Indigo, and Cushion Spurge.

I tend to shear to the ground any plant that gets leggy. 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 tend to crumble under the weight of the seed heads. After you shear a plant, give it extra water. If you do, within a week you will have new growth and in two weeks you will have a mound of fresh compact foliage.

Perennials to Shear: Hardy Geraniums, Lungwort, Brunnera, Catmint, and Lady's Mantle.

Author Mary Jo Buza is a landscape designer and owner of Gardens by Design. She has more than 20 years experience creating, installing and maintaining landscapes in Olympia. For more information on a custom landscape design, consulting visit or her low cost plant shopping service call Mary Jo at 923-1733.