Yeah, most homes in the northern U.S. have well-trimmed and tidy Kentucky bluegrass lawns, but Kentucky bluegrass does nothing for a self-sustaining landscape although it does have its place when used wisely and sparingly. But grass can and should have a fundamental part in a sustainable landscape – perennial clump grass that is!
Underused and Underrated in the Home LandscapeWhile ornamental clump grasses have had some success in professionally designed landscapes, their usefulness and productivity has been neglected in typical homeowner plantings. Let’s start by defining what a clump grass is and what the best characteristics are for a residential landscape grass:
- Clump grasses are named for their tendency to form clumps rather than spread evenly as a turf. The densest part of the clump is in the center for the first couple of years, then it tends to get to thin in the center for new shoots to push through. This gives them a fountain or mounded shape when they are young, often forming a ring-like appearance as they age.
- The best grasses for ornamental landscaping get at least 18 inches high. The taller they get, the better.
- Grasses used should be drought tolerant and considerate of climate.
Now let’s look at what grasses do for the residential landscape:
- Clumping perennial grasses have deep roots. How deep they go usually corresponds to how tall they are. Deep grass roots are the ideal builders of topsoil, and clump grass that stays in place for a number of years will have a long term impact on the quality of the soil for some years to come.
- The tops of tall perennial grasses also build incredible topsoil. Some of the greatest farming soils in the world were created by tall clump grasses in the American Midwest.
- Grass is a traditional fire starting material before the days of strike-able matches. It can be used as kindling as well as tinder.
- At least one grass, Indian ricegrass, is a nitrogen fixer and will help build the fertility of the soil it is planted in. When the soil gets rich enough the Indian ricegrass will decline and die. When that happens it is time for a planting that can handle a richer soil.
- Some grasses have edible seeds. They are not usually of the quality that we expect from our modern grains, but they fill in if things get rough.
Native ExamplesNow I know this doesn’t all matter without at least a few examples. The ones I have chosen are better for my area, and I chose them simply because I am more familiar with them. Feel free to look for what is available for your area, and remember, if you get a grass that is native to your area you may be able to leave it alone once it is established.
- Indian Ricegrass, Achnatherum hymenoides (Oryzopsis hymenoides); 1-2.5 feet tall, 18 inch minimum roots; nitrogen fixer, edible seeds.
- Little Bluestem, Schizachyrium scoparium (Andropogon scoparius); 1-4 feet tall, 14 inch minimum roots; red to bronze color in the fall.
- Big Bluestem, Andropogon gerardii; 3-8 feet tall, roots 2-4 feet at the end of the first growing season; makes a prime nesting sight for smaller wildlife.
- Big Bluegrass, Poa secunda; 1-2 feet tall, 10 inch minimum root.
So get out there and find a local ornamental grass and put it to good use making your landscape more productive and sustainable.