Turf has a calming, even essential quality. Most landscapes require some. For the past
couple decades, we have reduced turf to areas used for entertaining or installed alternatives that require less care than the standard monoculture of Kentucky bluegrass (actually from England). Costs associated with standard lawns include: weekly mowing and watering, fertilization, herbicides to control weeds, insecticides fungicides and various other control techniques where moles or other animals are uprooting the manicured look. Natural lawns and be a mix of native diversity, monoculture of sedge or other low growing native grass species, or–our favorite–”No-Mow,” a blend developed by Prairie Nursery in central Wisconsin. This mix includes several species of fine fescue; tough plants for well drained loam in the sun. Once established, this blend requires no irrigation, fertilizer or mowing. It can be cut to yield a more manicured look, but should be cut high.
Here in the upper Midwest, we are blessed with a tremendous diversity of over 300 sedge species. Their habitats range from the soggy edge of marshes, to raingardens (being mostly dry but occasionally flooded) to dry sand. Pennsylvania sedge is perfect for dry, sandy soil in full sun with no irrigation. It is difficult to establish from seed, but will fill in from plugs transplanted at 12-18″ apart.
The most difficult habitat for a dense turf appearance is deep shade with heavy clay soil. There are a couple of sedges we are testing that show promise for lawn alternatives in even these sites. The principle is that if the habitat exists, some plants have evolved to successfully colonize that setting. The longer term questions is whether that species will hold on to that site or will the site ecologically succeed into some new mix of plants. It is easy to see this progression where plowed fields are left fallow. A series of plant species move into the initially bare site. These can include trees like box elder and white pine, or annuals like rag-weed and mustards. Out of this list most are gone within just a few years. White pine are the exception, persisting for hundreds of years once their bark is thick enough to withstand ground fires.
In a garden setting, we can control this ecological succession by picking which species are allowed to become established, set seed or spread through rhizomes (in the case of sedges) or above ground stolons (in the case of strawberry). Each step of the way does require energy input. Our goal is to find a plant that will persist, once established, with the least amount of care. Native grasses are a potential solution, however, being bunch grasses, they grow with space between them and wait to come out of the ground until ground temperatures indicate spring fires have passed.
Fire is a great way to singe off undesirable trees, but having to wait until late May for controlled burns is a significant drawback. Non-native, high maintenance turf will green up weeks earlier than the native grasses.
Sedges seem to have the greatest promise for meeting every goal. Stay tuned to see what mix of species we find to be best for your habitat!
Please visit these other contributors to the Garden Designer’s Roundtable for more perspectives on Lawn Alternatives: