Follow these simple steps for a strong, healthy lawn that won't depend on chemical pesticides.
When watering a lawn, water infrequently, but deeply. This means water less than once per week, but when you do water, water to a depth of 1 inch. An empty tuna can is approximately one inch deep. Place the can beside your sprinkler and stop watering once it is full. Infrequent, deep watering results in deep root growth.
During extended dry periods in the summer, allow your grass to go dormant (brown). Watering only once per month (about ¼ to ½ inch is sufficient) will keep your grass alive and allow it to green up once fall rains return. The best time to water is in the morning.
Fertilizing is important to overall grass health and is a very effective way to prevent weeds. Fertilizing provides the nutrients for a healthy, thick lawn that out-competes weeds. Choose slow release fertilizers that are much less likely to 'burn' the lawn. Check the package labelling to make sure the product is slow release.
Apply fertilizers in the spring and fall. Carefully follow the instructions on the package. Use a spreader to avoid burns, missed areas, and spotty green patches. Fertilizing your lawn by hand is never a good idea.
Topdressing involves spreading good quality topsoil or compost on top of your lawn. This adds organic matter and improves the condition of the soil. Look for bags of top dressing that contain a blend of compost, soil, and peat moss. Topdressing is essential on bare areas and on lawns with little topsoil. Add ¼ to ½ inch of topsoil or compost. Don't smother the grass blades.
Always use good quality compost to ensure it is weed-free. Avoid using non-composted manures; they may contain weed and crabgrass seeds.
- Prepare the area by removing any dead pieces of sod/grass and any other debris.
- Add topsoil and level the area to match the existing sod.
- Spread grass seed. If available, use a seed spreader to spread the grass seeds. If not available, apply approximately 15-20 seeds per square inch by slowly releasing from your hand. Spread as evenly as possible.
- Tamp down slightly using a gardening tool.
- Keep the repaired area moist until the seed starts growing.
Early fall is the very best time to overseed, but it can also be done successfully in the early spring.
Topdressing and overseeding can be done together. Add grass seed to your lawn and then cover with topsoil or compost. Alternately, mix the seed and the soil and spread them on the lawn together. Gently rake a thin layer of the mixture over the entire lawn or just on problem areas. Ensure the seeds remain moist for several days either through rainfall or daily light watering.
Raising the height of your mower is one of the simplest and most important things you can do for your lawn's health. Adjust your mower so that it cuts your grass at 2.5 to 3 inches (6 to 8 cm) high. Longer grass blades result in deeper root growth. Longer grass also creates shade that prevents weed seeds from germinating.
Instead of bagging your grass clippings, leave them on the lawn. Unless they are exceptionally long, grass clippings won't cause any problems. In fact, they can provide about one-third of your lawn's nutrient needs and are a valuable source of organic matter.
Aeration is the process of removing plugs of soil from your lawn. This creates spaces for air, water and nutrients to penetrate into the soil and promotes the growth of beneficial microorganisms. It also increases water absorption and reduces surface runoff.
Aeration is essential for compacted soil. Signs of compacted soil are: bare patches standing water after rain decreased grass vitality.
To test for compacted soil, stick a screwdriver or pencil into the soil. If the soil is compacted this will be difficult to do.
Aeration is also essential to reduce thatch problems. Thatch is that tough layer of dead organic matter between the lawn and the soil. When thatch becomes too thick, it blocks water and nutrients from getting to the soil.
Avoid aerating when your soil is very dry. Wait until after it has rained or water deeply the day before you aerate. Spring and fall are the best times to aerate.
Thatch is a tough mixture of dead grass and roots that accumulate and form a layer at the soil surface. In a healthy lawn, insects, earthworms' beneficial fungi and other microorganisms break down thatch and aerate the soil naturally. One cm (1/2") or less of thatch is normal and requires no treatment.
A number of conditions, such as excessive watering, too much nitrogen or excessive pesticide use, may lead to a situation where the thatch exceeds 1 cm. This may prevent water and nutrients from getting into the soil and down to the root system and it can also harbour harmful insects so dethatching is required.