How to Cut Back Ornamental Grasses in Spring or Fall

how to quickly prune ornamental grass
The Spruce, 2018

Ornamental Grasses Need to Be Cut Back

Ornamental Grass in Snow

Ornamental grasses are an increasingly popular choice in today's garden, where their textures and colors provide a visual interest that is much different from that of other plants. And because many ornamental grasses are native species, they are very popular among gardeners who are interested in natural landscaping or water-efficient gardening. But once the foliage fades and turns brown at the end of the growing season, a gardener is left with removing the dead grass, a job that can be time-consuming and messy. The job is much easier if you bundle up the stalks before you cut them off. 

When to Cut Back Ornamental Grasses

It's a matter of personal choice whether you cut back your ornamental grasses in fall after they die, or to leave them in place through the winter and cut them back in the spring. Many ornamental kinds of grass will remain attractive if left standing throughout the better part of the winter. At a time when the rest of the landscape is rather dreary, long grasses swaying in the breeze can add some visual interest. Long grasses with seed heads may even provide food for the birds, but remember that long-dead grasses can also provide shelter for mice, voles, and other rodents.

If you do choose to leave your ornamental grasses standing through winter, you will still need to cut them back by early spring, before the new growth begins to blend in with the dead grass. Wait too long, and it will be impossible to remove the dead grass without also shearing the new green grass.

Project Metrics

  • Working time: 15 minutes or less per plant
  • Total time: An entire garden bed filled with ornamental grass requires a couple of hours to cut back
  • Material cost: None, unless you need to purchase pruning shears (generally less than $30)

What You'll Need

  • Biodegradable tape or bungee cords
  • Pruning shears or power hedge trimmer
  • Lawn rake

Bundle the Grass

An Easy Way to Cut Back Ornamental Grasses
The Spruce / Marie Iannotti

The more full and beautiful an ornamental grass is, the messier it is when cutting down. To lessen the mess, start by bundling the stalks together.  Any wide tape will do, as long as it's sticky enough to adhere to the grass. Biodegradable tape is recommended—paper rather than vinyl tape. As an alternative, many gardeners like to use bungee cords. Wrapped tightly, they should hold together long enough to reach the compost bin, where you can spring them loose.

Depending on the width and height of the ornamental grass, you may need to wrap each bundle of grass in two or three positions along the length of the plant stems. And large plants may need to have their stalks divided into two or more bundles. The grass plant shown here is relatively young and can be bunched whole.

Cut off the Grass

How to Cut Back Ornamental Grasses
The Spruce / Marie Iannotti

Now that your ornamental grasses are neatly bundled, it's much easier to take your pruning shears and prune the grass back at ground level. With the tape or bungee cords holding the grass blades in place, lean the bundle away from the base as you cut with shears.

If your ornamental grass is well established, you may prefer to use a power hedge trimmer to do the job. Either way, bundling the grass in this way makes for an easier job than grabbing handfuls of grass blades and cutting each by hand. 

Finish up the Job

Cutting Down Ornamental Grasses
The Spruce / Marie Iannotti

Now all you are left with is a neat and tidy bundle of grass. There will undoubtedly be a few renegade blades to clean up with pruning shears, but nothing like the messy sprawl that occurs when ornamental grass is cut haphazardly. 

Picking up the ornamental grass bundles to take to the compost pile is an easy enough task, but removing the tape can be a major hassle. If you've used paper-based masking tape, you can usually just add the entire bundle to the compost pile, since the tape itself will decompose. If your only option is a vinyl tape, then remove it as best as you can; any small remnants can be screened out when you eventually use the finished compost. 

Finish by raking the garden area to catch any loose blades of grass and other debris. 

Tips for Bundling and Cutting Ornamental Grasses

  • This same bundling technique works well for any plant with many shoots that need to be cut back to ground level in fall or spring. For example, Siberian iris with its many long, sword-like leaves is easiest to cut back if you first bundle the leaves together. 
  • Cutting up the dead grass stalks as you add it to the compost pile can speed decomposition and make it easier to blend it in with other materials. It's much easier to do this if the grass stalks are already tied together in bundles. 
  • Dried dead grass comprise a "brown" component in a compost pile. When composting large volumes of dead grass, balance the mixture by also adding plenty of green material. Or, adding a few handfuls of nitrogen fertilizer to help the grass break down faster. 
  • Most ornamental grasses are perennial plants, but a few are grown as annuals, especially in cold northern climates. For these, it is best to dig out the roots of the plants after bundling and cutting off the stems.