Fall cleanup — an essential part of maintaining a healthy landscape
Things like trimming away dead branches and eliminating rotten leaf debris that can harbor pests, mold spores, and mildews will set up your plants and lawn for success when the spring growing season arrives. There’s one exception to the fall cleanup chore list: You can choose to leave your ornamental grasses standing tall all winter long. There are pros and cons to trimming them in the fall, and Quality Care’s plant care experts can help you make the best decision.
Leave Them Be
Many kinds of ornamental grasses grow well in Iowa and surrounding Midwestern states thanks to our prairie heritage. From burgundy switch grasses to dwarf zebra grasses, these plants bring color, height, leaf variety, and visual texture to planting beds and container gardens. If you wait until spring to trim them, they can provide shelter and nutrient sources to non-migrating birds and small animals. Some beneficial and native insects overwinter in the plant debris of grasses and other perennials, so it is recommended to wait until air temperatures are consistently at 50 degrees before removing the stems.
Most ornamental grasses go dormant over the winter, so you don’t need to water or care for them. Just let them be and enjoy the waving stalks and snow-dusted mounds throughout the season.
Cut Them Back
Fall may be the best time to cut your grasses if you like a clean, tidy look. As winter progresses—particularly if there are temperature swings that lead to cycles of freezing then melting then freezing again—the leaves and stalks of ornamental grasses will get messy. Stalks bend and break, leaves fall over, and foliage on the ground gets wet and rotted. This can make spring cleanup harder because the limp, slippery stalks are now a challenge to clip neatly.
While none of the wintertime bending or breakage damages the plant, it may not look as good in late winter/early spring as it did in early winter.
Trimming Tips
No matter what time you decide to cut back your ornamental grasses — fall or spring — you won’t hurt them as long as you do it correctly:
- If you wait until spring, be careful to remove the old growth before the new growth is sticking up tall enough to get cut off. You won’t hurt the grass, but the tips of the leaves will have a chopped look.
- When you make the cuts, use sharp shears or an electric hedge or string trimmer to cut straight across the dead stalks. Make the cut about 6 inches above the ground for shorter grasses like prairie dropseed, and about 6 to 10 inches above the ground for taller grasses.
- DO NOT cut them back all the way to the ground. The part of the plant where the stems meet the ground is called the crown, and it is a vital part of the plant. Cutting grasses at the crown could result in fatal cold damage.
