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For many people, maintaining a lush, green lawn is a source of pride. Many of us spend a great deal of time and money to achieve this ideal. But as we learn more about the dangers of pesticides and polluted runoff, many of us are seeking lawn care alternatives that won’t harm our families and communities. Fortunately, a truly healthy lawn is both beautiful and safe. Here are five simple steps to get you on your way:



Keep your lawn at least three inches high. Mowing high produces deeper roots, so that the lawn is more resistant to drought and disease. Taller grass also shades out most weeds!



Keep blades sharp and mow only when grass is dry to reduce damage to the plants. Avoid mowing during intense heat & drought. And leave clippings on the lawn. They enrich the soil with nitrogen, and won’t cause thatch if you fertilize correctly and avoid pesticides. (Pesticides kill beneficial organisms that break down organic matter.)

Follow the one-third rule: Never cut more than one-third the length of grass blades. So if your mower height is set to the recommended three inches, cut the grass before it gets to be more than 4.5” high.

Consider trading in your gas-powered mower for a reel or electric mower, especially if you have a small lawn. Gas mowers make as much pollution in one hour as a car driven 100 miles! Reel mowers also cut grass in a way that is healthier for your lawn.



Your lawn will stay healthiest and prevent runoff best if you replace depleted nutrients in the soil. A $15 soil test will tell you precisely what your lawn needs, and should be performed every few years. (Contact your county extension office. In Milwaukee County, call 414-290-2400. Or visit this website for downloadable instructions.)

Use low-phosphorus fertilizer. Most lawns in this region do not require phosphorus, or need it very infrequently, and phosphorus runoff causes algae growth and fish kills in Lake Michigan. Keep fertilizer off sidewalks and other paved surfaces, and avoid applying it to bare soil. Remember, in most parts of Greater Milwaukee, storm sewers deliver storm water into Lake Michigan and its tributaries untreated.

A typical lawn in SE Wisconsin needs 4 lbs of nitrogen per 1000 square feet per year, but leaving grass clippings on the lawn reduces the need to just 2-3 lbs, and shady lawns need even less. Organic fertilizers (eg, corn gluten meal) release nutrients slowly and won’t “burn” your grass. Organic fertilizers can be harder to find; try a garden center or natural foods store rather than a hardware store.

Focus on the fall. Research shows that spring fertilizing increases leaf growth, which can help the grass shade out weeds, but it does little to help the turf’s roots. Fertilizing in fall, on the other hand, strengthens root systems and also promotes healthy growth the following spring. (See our lawn care calendar for ideal times to fertilize.)

Avoid “weed and feed” fertilizers. Many people don’t realize they contain pesticides. These products lead to pesticide overuse and improper timing of fertilization. Weeds are the result of an unhealthy lawn, not the cause of it. Read more about the pitfalls of weed and feed here.



Most lawns ideally need one inch of water per week, except when dormant (see below). Water deeply once a week, if there is little rain, to promote deeper roots (as shown below, left). Frequent, light watering is a common mistake that does more harm than good, by encouraging shallow roots (below, right) and grass that is more vulnerable to drought and stress.



Early morning is the best time to water. Watering during the day tends to be inefficient due to evaporative loss, and evening watering can encourage fungal diseases. Use an empty tuna can or glass to determine when your lawn has received one inch of water. Water slowly to avoid runoff. Clay soils may require watering in two or more cycles to allow full absorption.

Water applied to streets, driveways, and sidewalks is certain to run off into the storm sewer system, contributing to pollution of Lake Michigan. Try to position your sprinklers so that watering of impervious surfaces is minimized. This may require turning down the water pressure to water a smaller area and moving the sprinkler around to reach all areas of the lawn.

Aeration and overseeding are additional ways to improve your lawn. (See our lawn care calendar for the best times to perform these tasks.) Aeration evens out lumps in the lawn, allows water & nutrients to reach roots, and decreases thatch. Aeration is especially important in high traffic areas, clay soils, and lawns transitioning from pesticide use. Use a manual core aerator or rent a power aerator from a hardware store. (Share the cost with your neighbors.) Aim for 6 cores per square foot. Cores can be left to dissolve on the lawn, or raked and composted.

Overseeding is essential for keeping turf thick and crowding out weeds. First mow grass to 2” and rake to improve seed-to-soil contact (aerating first is also a good idea), then apply a quality seed blend appropriate for the amount of light your lawn receives. Apply 2-3 lbs per 1000 sq ft. You may then wish to topdress with topsoil or compost. (Compost is especially useful for loosening clay soil and repopulating soil organisms in lawns recovering from pesticide use.) Mulch bare areas with straw. Keep moist and avoid foot traffic for 3-4 weeks. Mow when new grass is 3” high.



A healthy lawn is rarely 100% weed free. Ask yourself whether some “weeds,” like clover or violets, might be acceptable. In fact, allowing for a diversity of plants is a healthier and more natural approach than the pursuit of an artificial “monoculture” of turf grasses. Consider replacing areas of your lawn with groundcovers or other plantings, especially in areas where grass tends not to grow well (e.g., shade). Pull weeds manually or use organic products like vinegar spray and corn gluten meal. Corn gluten meal is an organic, non-toxic product that prevents weeds from germinating, and also acts as a slow-release organic fertilizer. When used consistently for 3-4 years, corn gluten meal is very effective at controlling most weeds. (See our lawn care calendar for timing application of corn gluten meal.)

Most importantly, realize that building a healthy lawn, especially one that is transitioning from pesticides, takes time and patience.

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