When Should I Cut Back My Ornamental Grasses?

“I have lots of ornamental grasses in my garden. When is the best time to cut them back?” Question from Mary of Raleigh, North Carolina

Answer: Tall ornamental grasses, like Chinese silver grass (Miscanthis sinensis) and switchgrass (Panicum virgatum) provide food and cover for many birds and other wildlife. Their dry blades and seedheads also tend to look pretty through the winter months. So, the best time to cut them back is in spring when your bulbs just begin to peak up from the soil. Take some sharp shears, wear protective gloves, and cut them back to about 8-12 inches from the ground. I suggest composting them. The tops quickly break down in the compost heap, especially if you cut them up into smaller pieces and keep them moist.

Many smaller bunch grasses, like blue fescue (Festuca glauca) and prairie dropseed (Sporobolus heterolepis), do not require cutting back, while mid-sized bunch grasses, like fountain grass (Pennisetum alopecuroides) do.

Make sure you rake away all remnant grassy blades to keep your beds looking tidy!

Happy gardening!

Jessie Keith

Black Gold Horticulturist