The polyculture lawn: A primer

December 13, 2010

NOTE: Images in this archived article have been removed.

Image RemovedBee in Creeping CharlieDuring a recent conservation/climate change seminar, I happened to comment about the relationship of home gardens to natural areas; how we need to cease thinking of nature as being something over there, while our private yards and gardens are treated as separate; and how our gardens can act help sequester carbon. Afterward, a woman came up to me, someone who had spoken knowledgeably about habitats, biodiversity of prairies, and the difference between C4 and C3 plant species. “Without using herbicides,” she said, “What am I to do about the creeping Charlie in my lawn? I just hate it.”

A fellow gardener and I tried to explain: a polyculture lawn is ok—herbiciding creeping Charlie not worth the environmental cost (besides which it’s nearly indestructible)—it’s easy to pull up—it mostly grows in shady areas where grass has difficulty—bees like the flowers—looks nice in spring—don’t fight it…Well, she wasn’t going to hand weed it, thought she was allergic to it and lawns shouldn’t have flowers in them. We gave up; we had encountered another urban/suburban dweller who hadn’t yet realized that one of the best ways to do something about conservation and climate change is to change how you take care of your own land.

Now, as we transition towards a less oil soaked, lower carbon way of life, many of us will realize, possibly of necessity, that of course there are all kinds of things we could do with our valuable urban and suburban land instead of having a lawn. However, until the day that there are chicken coops, beehives and clotheslines in every backyard, vegetable and pollinator gardens out front and bioswales along the side, I’m assuming most people will have a lawn of some sort. The thing is, as I’ve ranted here, there are conventional lawns and then there are post conventional, ecological lawns. After reading that post, a number of people asked, “Ok, so what is an ecological lawn and how do you make one?”

My answer is that an ecological lawn is, above all, intentional and mindful. The ideal ecological lawn is appropriately sized for its purpose, thoughtfully placed, polycultural, and cared for by organic means according to natural seasonal cycles and time frames with inputs furnished from the property. A polyculture lawn, which some call a clover lawn, provides ecological services, increases biodiversity, helps manage and conserve water, and stores carbon. Not only that, it looks good, it’s safe for children and animals, and it’s cheap. All you have to do is move beyond the idea that a lawn should comprise grass and grass alone.

The Process

Decide where you need and want a lawn. In general, a lawn should not be the major element in the landscape unless you are planning to pasture animals. Some small properties may not require a lawn. Where a lawn would be extraneous, make plans—why I’m writing this in winter—for a food garden, or for areas planted with native trees, shrubs, flowers and grasses. Resolve to cease all chemical, fossil-fuel-based inputs: synthetic fertilizer, herbicides and pesticides.

Image Removedpolyculture lawnIn spring, rake the lawn with a metal rake to expose some bare soil. Next, top-dress with compost put through a screen to break up large bits. If you don’t have compost, you can use composted manure or other composted organic materials, available at garden centers. You can also buy organic fertilizer to use until you have a good supply of homemade compost, though it’s more expensive and not necessary. If at all possible, start a compost system, beginning with the debris you’ve raked up. Compost is part of the ecosystem services, carbon storage part. Then, overseed the lawn with a low maintenance grass seed mix that includes turf fescues and white Dutch clover (at this point I can imagine pasture farmers such as Gene Logsdon chuckling at us city folks). If the mix doesn’t include clover, get a small amount and sow it evenly over the area—it is a vitally important component of the polyculture lawn. Water regularly until the clover establishes itself. If you live in a neighborhood full of chemical lawns, you may wish to put out a small sign that says something like “healthy lawn in progress” for your neighbors’ benefit.

When the new growth reaches about 4 inches, mow, using a push reel mower if possible. Mow to 3 inches, no shorter, to allow the grass enough length for good photosynthesis. Whenever you mow, let the clippings fall to decompose and add nutrients back to the soil. After the clover has come in, don’t water—the clover will help keep the lawn green. Hand dig any broadleaf weeds such as dandelion, plantain, and especially thistle, that get too far out of hand. May and again in September are good times for this. Don’t worry about creeping Charlie and violets. They’ll blend in. In summer, mow often enough to keep the grass at 3 inches. In fall, top dress again with screened compost and rake up fallen leaves—by hand please, no leaf blowers allowed—to go in the compost bin. Alternatively, you can run the lawn mower over the leaves so they are chopped up and will nourish the soil over the winter. Fall is also a good time to plant small bulbs such as snow drops, scilla and chionodoxa, which finish blooming before the first spring mowing. Next spring, repeat. Overseed as necessary. Be patient, as it may take up to three years to convert over, and for the soil to regain health.

Image RemovedA beautiful lawnThe Results

As you follow these recommendations, the lawn will transition into a post-conventional polyculture lawn, healthier in every way. In spring it will be full of small flowers, along with bees, butterflies and birds. A plain green lawn will come to seem boring.

This works because grass and clover co-evolved to grow together. Clover, as pasture farmers know, but many lawn-owners don’t, nourishes the grass by fixing nitrogen, and helps with water management. Its roots, two feet deep, also help store carbon and bring nutrients up to the surface where the grass’s shallower roots can access them. The whole lawn stays greener all through the summer. Rain soaks in and helps sustain the water table, instead of running off as with conventional lawns.

The soil will improve, gradually developing a higher percentage of organic material, thus storing more carbon. As it does so, what was literally dead soil will become alive with earthworms, microorganisms, fungi, arthropods and other tiny critters, who, amazingly, by living their lives and doing their work, will help keep the soil ecosystem balanced and help reduce problems with grubs and ants that can become pests if populations get too large. In addition, thatch will no longer be a problem, in part because of the earthworms.

Animals and beneficial insects will also benefit. Bees, both native and honey, love clover, and with populations declining, they need as much extra habitat they can get. Clover also serves as a larval food host for several species of sulfur butterflies. Butterflies also respond well to polyculture lawns where creeping Charlie and native violets bloom in spring. In fact, fritillary butterflies’ main larval food is the common violet. As the lawn ecosystem improves, more bird species will show up, flickers for the ants, robins for the earthworms, grackles for the grubs—they’ll help keep the insect population in check. The insects they feed their young won’t be full of toxic pesticides, so hatchlings will be healthier too. Rabbits like to eat broadleaf weeds and will help keep them in proportion. And of course, there are the children and dogs whom we love.

Converting a conventional lawn to a post conventional polyculture lawn will also help the larger ecosystem, preventing chemical and nitrate runoff and helping provide the green corridors that other species need. Whether a dwelling sits on a suburban quarter–acre or a 25’x125’ city lot, the inhabitants are responsible for that land, and are, by default, its stewards. With the right care, we have the opportunity to sequester carbon, improve ecosystem health and to contribute to the biotic community. A polyculture lawn is beautiful in the spring, naturally greener in the summer and healthier all year. And if you ever do decide to turn it into a vegetable garden, the soil will be much more fertile, and more suitable for organic gardening.

Adiran Ayres Fisher

Adrian Ayres Fisher

Adrian Ayres Fisher serves as a volunteer steward of a small forest preserve on the banks of the Des Plaines River in Illinois. As programs co-chair of West Cook Wild Ones, she educates about and promotes native-plant gardening and biodiversity. She writes and speaks on a range of nature-related topics from a Midwestern point of view. Her home is in an inner-ring suburb of Chicago and she blogs at Ecological Gardening.

Tags: Building Community, Buildings, Urban Design