The beauty of ornamental grasses is apparent in winter. But winter can take its toll on the delicate ornamental characteristics of these plumed wonders.
Species like Revenna Grass (Erianthus ravennae), Fountain Grass (Pennisetum setaceum), and Plume Grass (Miscanthus species) grow large plumes of intricate structure. These create color and wind-driven motion in the otherwise rigid and stark wintery landscape.
Depending on the amount of snow, wind, and driving rain they endure, the plumes of ornamental grasses can lose their delicate characteristics as winter wears on. They need to be cut back in late winter, even if they appear to remain in good shape.
Cutting back grasses is essential to provide growing space for new foliage and plumes in the coming year. It also removes dead foliage and stems, giving the new growth a clean and green appearance at the start of the new season.
Tips on Cutting Back
The task of cutting back ornamental grasses in the landscape can be messy and labor intensive, but there is one method that can be used to minimize mess and save time:
First, find a length of biodegradable twine, at least 4 feet long. Tie a loop at one end. Place the twine around the base of the clump and put the end through the loop, like a lasso.
Slide the lasso up the clump about half way, bundling the leaves and stems as much as possible. Cinch the twine tightly around the clump, and tie it off there.
Use sharp tools like power trimmers or hand pruners to cut the clump three to four inches above the ground. String trimmers are seldom sharp enough to cut the clump, and fragments of dried leaves and stems get scattered, making clean-up difficult.
Leaving this stubble in place protects the new season's growth from late freezes and keeps it physically sheltered during the fresh growth stage.
Remove the clump, keeping it tied and intact, and place it in the compost pile. It is a good idea to keep the twine in place to prevent the grass from blowing out of the compost pile.
If applying fresh mulch around the ornamental grasses in spring, use the stubble as a reminder that the grass is there, and avoid covering the plant with mulch.