Overseeding is the planting of grass seed directly into existing turf, without tearing up the turf or the soil. It’s an easy way to fill in bare spots, improve the density of turf, establish improved grass varieties, and enhance your lawn’s color. Overseeding is done with specialized slit seeding machines or simply broadcast over the yard after core aeration.
Many older lawns were established with common type turf grasses not suited for the needs of today’s homeowner. They’re often more disease and insect prone, requiring more fertilizer and water. Overseeding newer turfgrass varieties into an older lawn can help it better withstand insects, disease, drought, shady conditions, and heavy traffic. Even in a healthy lawn, overseeding is recommended periodically to promote age and species diversity.
When Should I Overseed?
- Late summer or early fall is the best time to overseed lawns. Soil and atmospheric temperatures are most favorable for optimum seed germination and growth. With adequate moisture, fertilizer, and sunlight, the new seedlings will be well established before cooler fall weather sets in. Also, weed competition is less of a factor at this time, giving the grass seedlings a better environment to grow and develop.
- Spring overseeding risks the chance of weather-related problems (heavy spring rains, unexpected high temperatures) and weed competition. Also, spring seeding may interfere with the application of pre-emergent crabgrass or broadleaf weed killers; concurrent application of seed and herbicides is generally not recommended because the herbicides may cause poor seedling establishment. It is best to delay herbicide treatment 4-6 weeks after new grass seed germinates. If you choose to overseed in the spring, be sure to follow proper seeding and treatment practices.
- Midsummer overseeding faces greater chances of disease, heat, and drought stress and weed competition. Proper weed control and adequate irrigation are musts if overseeding is attempted in midsummer. In most cases, this is not recommended.
- Dormant overseeding involves seeding in late fall or early winter, after soil temperatures are low enough to prevent seed germination. Due to our climate fluctuations, this method is generally not recommended.
Overseeding vs. Lawn Renovation
Overseeding is commonly used to improve a lawn that has been adequately maintained. Lawn renovation may be the better option if your lawn has excessive weed presence, drainage issues, bare spots, thin turf, compacted soil, or is very “bumpy.” Our lawn renovation packages will correct a problematic lawn from the soil up.