Annette Ipsan
Frederick County Master Gardener Program

Getting your garden ready for winter is important to the health of your plants. How and when you cut things back is determined by the individual needs of your plants, your desire to provide food and cover for wildlife, and your appreciation for winter interest.

Common practice formerly dictated cutting everything back to the ground for a neat appearance. Then we began to realize that butterflies lay eggs on leaves, birds feed on seeds and berries, and many animals use plants as cover. Also, winter interest - the beauty and drama created by seed heads, grasses and perennial stems left standing for winter - came into vogue. So, now aesthetics and concern for wildlife curb our urge to snip everything in sight.

So, should we cut anything back? Yes. Plants that had a serious disease or insect infestation should be cut back and the trimmings bagged with your trash. Plants with no winter interest should be trimmed, too. Some prime examples are veronicas or geraniums that blacken and turn to mush at the first cold snap. Also cut back vigorous reseeders. My pink threadleaf coreopsis would take over my perennial beds if I didn't use a firm hand in fall trimming.

There are five categories of plants that should not be cut down for winter. First, leave standing any plant you feel contributes aesthetically. Grasses give wonderful architecture to the winter garden, so wait to cut them back until spring. Interesting seed heads and branches of arching perennials and shrubs also add winter interest, so spare them, too. This is all very subjective. Cut what you don't like. Leave what appeals to you.

Avoid cutting back tender perennials or ones that are not reliably hardy such as mums, monch asters and ferns. The old foliage helps to protect the crowns through winter. Show discretion when cutting back plants that are late to show in the spring. Plumbago and blue wild indigo are just two plants that are notorious for worrying gardeners by sprouting later. So leave a good chunk of their stems to mark their location so you don't disturb them or plant something on their heads.

Some plants such as sundrops have attractive evergreen foliage at their base. If you prune these plants well throughout the summer, there is no need to cut them back further. Let their whorls of foliage bring a little color and beauty to your winter garden A few shrubs bloom best on new wood. Bluebeard and butterfly bush, for example, will bloom more heavily if you wait to prune them until spring. Spare them a fall cutting and they will deliver winter interest and a bountiful flush of new growth and blossoms.

The timing and method of cutting plants back for winter is important, too. Later is better, generally. If plants are cut down too early, it can stimulate growth, use up energy reserves and keep the plant from coming back in the spring if a hard frost hits the tender new foliage. So, avoid cutting back plants too early. Some gardeners wait until the first hard frost - October or November in this area - but I usually start my fall clean-up whenever it starts to get cooler in late September or early October.

How low should you go? A good rule of thumb is two to three inches from the ground. That leaves some stems to act as a marker and avoids damaging the crowns or any overwintering buds that may lurk at or just below the surface.

With the cooling temperatures and falling leaves, fall gardening is a real pleasure. Tidying your garden with an eye toward preserving beauty and wildlife makes it a task that adds valuable habitat and attractive winter interest.

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