Alternative Lawn Care: 4 things to think about
by Brad T. DeBels, Department of Soil Science, University of Wisconsin–Madison
A healthy, attractive lawn provides many benefits, including a place for relaxation, a filter for air and water, a safe place for our children to play, and increased property value. Everyone wants to take advantage of these benefits, but over-managing the lawn can create problems too. With the month of May now here, and having just celebrated Earth day and National Lawn Care Month in April, it is a good time to discuss environmentally friendly approaches to maintaining a high quality lawn.
Focus on the Soil
First, it is important to know that the number one lawn problem is not a weed, insect, or disease. The majority of lawn problems are caused by poor environmental conditions, including insufficient light, poor drainage, or compacted soil. Of these, the soil often plays the most important role in lawn care management. During home construction the topsoil is usually stripped off, leaving a compacted, nutrient-poor growing medium (Figure 1, below). Sometimes a thin layer of topsoil is replaced, but it is often only a few inches deep and inadequate for good turf growth. For a healthy lawn, you will want a minimum of six inches of good topsoil consisting of more than 50% silt, less than 10% clay and more than 2% organic matter. Topsoil fitting these characteristics can be purchased, but when considering soil and delivery costs, it can be very expensive. If this is not feasible, the next best solution is to core cultivate (or aerify) the lawn to alleviate compaction in the surface layer. Also adding about one-quarter inch of high quality compost in the spring and fall of each year will slowly improve poor soil conditions.
Right Grass for the Right Place
Grass species and cultivar selection and establishment are also very important considerations for any lawn care program. Be sure to plant the correct turf plant in the right place. To successfully out-compete weeds during establishment without chemicals select a turf that germinates quickly or consider sod (Figure 2, below). Your grass selection must also reflect your mowing, irrigation, and fertilization management practices. In general, the University of Wisconsin Extension recommends fertilizing your lawn two to three times each year, but some grasses do much better than others with less frequent fertilization. Figures 2, 3, and 4 (below) illustrate the importance of grass selection reflecting your desired fertilization practice. Tall fescue and fine fescue can perform well when fertilized infrequently, while Kentucky bluegrass requires more applications to maintain its aesthetics and functionality. However, fine fescue will not tolerate high traffic or compacted soils well and tall fescue will not survive ice cover.
Fertilization and Pest Control
After you address any soil problems and have selected a good grass species, the next step is to fertilize it to maintain good density. In Wisconsin, we have many good organic lawn fertilizer options, including Milorganite, Chickity Doo Doo, Chick Magic, and others. Although they often carry a higher price per application than many synthetic fertilizers, they have performed well in University of Wisconsin research trials. Fertilization amount is a choice, and as we discussed, different grasses will respond differently to fertilizer. In general, the best times to fertilize are Labor Day, Memorial Day, and Independence Day. Skip the Independence Day fertilization if the lawn is brown from drought. Fertilize to maintain optimum density and make sure to mulch your grass clippings back into the lawn. They provide extra nutrients to the grass. If thatch begins to accumulate, cut back on the frequency of fertilization but don’t bag your clippings. Clippings do not contribute to thatch. Finally, it is important to remember that whether organic or synthetic, both forms of fertilizer pose risks to surface and ground waters when applied improperly.
The final component of alternative lawn care management is pest control, including both weeds and disease. The primary pre-emergent alternative weed control option is corn gluten meal, an accidentally discovered byproduct of corn wet milling in 1991. This product inhibits root formation of germinating plants by applying 12–20 lbs per 1000 ft2 in early spring and/or late fall, but can cost $25–$50 per 1000 ft2. Post-emergent options include herbicides that contain acetic acids, soaps, and plant oils, however, many of these products will also kill turfgrass. A cost-effective but laborious alternative for post-emergent control is hand pulling. While this is daunting task for large areas, it is more manageable on small lawns.
In summary, the key to a successful lawn care program is to begin with a deep, non-compacted, well-drained soil. Add the proper grass species and good fertilization practices and you’re well on your way to a beautiful and environmentally friendly place to relax and play.
For more information, please check out “Do-It-Yourself Alternative Lawn Care” available online for free at the University of Wisconsin-Extension Learning Store http://learningstore.uwex.edu/.