The Best Time to Cut Back Ornamental Grasses

Fountain grass

Because ornamental grasses add winter interest to the garden, the best time to cut them back is after they have had a chance to show off. Northern gardeners trim the grasses back in March or April, while those in the South do this as early as February.

Types of Grasses

Most ornamental grasses are perennial (meaning they come back every year), and these should be cut back in early spring, before new growth begins. Some grasses, however, are annual and are showiest in summer. Cut these back at the end of the growing season unless they offer decorative promise for the winter. The popular red fountain grass is one of the few annual grasses that is handsome in the North during winter.

How to Cut Back

Cut grasses back to a height of 4 to 6 inches. Use a sharp pair of pruners for established clumps. Hedge shears will work for a newer, less dense planting. If the clump is mature, tie a piece of twine securely around the old stems about halfway up from the ground before cutting the grass back. The newly cut stems will fall to the ground in a neat bundle and cleanup will be a breeze.

Failure to Cut

Sometimes even devoted gardeners fail to cut back the old stems of a perennial grass. This delays the emergence of the new growth and the appearance of the clump will be unsightly, with the previous year's dead foliage woven throughout the fresh new growth.

References

• University of Illinois Extension: Ornamental Grasses

Resources

• Bluestem Nursery: Grass Clippings