Garden designers often refer to movement as an element to consider when planning your garden. Plants are stationary. So how do you get movement? An easy answer is ornamental grasses. Picture a fall breeze rustling across a group of ornamental grasses causing them to wave gracefully suggesting flowing water. The result can be very beautiful. They also add beauty in winter, providing texture in a snow clad landscape.
If you have a steep bank, grasses are a great solution to end dangerous mowing situations while, at the same time, preventing erosion. Grasses, especially native grasses such as switchgrass, prairie drop seed, little blue stem and Indian grass have deep, fibrous roots (as deep as 5 feet) to hold the soil in place. They will come up by themselves every year and, unlike turf grass, you don’t have to mow them every week.
Ornamental grasses give shelter and protection to birds and beneficial insects, including butterflies, during summer storms and winter cold, so be sure to leave them stand all winter. Besides shelter, they also provide seed for the birds to eat. Highlight them during the winter by placing some up-lights in front of them.
Ornamental grasses need to be cut down in March just before their new growth begins. Tie a strong string, duct tape or cord around the whole grass clump, then use your hedge shearers to cut it as close to the ground as you can get it. The string will hold the grasses together and keep the clump neat as it falls. Cut grasses can be used as mulch in the paths of the vegetable garden, or, I cut them into slightly shorter segments, and use them for mulch under big shrubs.
When you cut your grass down, you may notice that it is dying out in the center and is beginning to resemble a donut. This is a good time to rejuvenate the clump and also to get more plants. Dig up the entire clump, then cut it into segments. Replant the section you want to keep. Plant some other segments in new areas of your garden, or give them away. Always keep newly planted segments hydrated the first year.
Ornamental grasses are often mentioned when discussing fall garden design because the warm season grasses are slow to develop in the spring and can take quite a while to mature. It generally takes until August or later for them to “flower” or develop their seed heads and mature color.
There are also cool season grasses available which tend to mature much earlier. My favorite grass in this category is feather reed grass ‘Karl Foerester’ (Calamagrostis acutiflora Karl Foerster). This grass will grow quickly through May up to 5 feet tall, then flower in June. I love it because it not only matures early, it stands straight up on very sturdy stems, and doesn’t flop over other plants. In fact, it makes a lovely backdrop for other flowers in front of it.
If you shop for ornamental grasses you will be amazed by how many varieties, sizes, shapes and colors are available. What to choose? When I want to buy any new plant for my garden, I always look at natives first and also consider the growing conditions the soil has to offer. Most ornamental grasses like full sun and neutral soil, but there are a few that prefer shady, moist areas. Have fun planning for movement in your next fall garden. With a little planning anything is possible.
For additional information or questions and the Master Gardener Program please contact Nebraska Extension, West Central Research and Extension Center at 308-532-2683.