There's a secret behind achieving a beautiful, lush lawn. Landscape professionals know what it is, but many homeowners don't. Overseeding—as part of a comprehensive, proactive plan—keeps lawns looking great. Whether you're tending your first lawn or have years of experience, learning how to overseed your lawn can improve your results.
Overseeding is spreading grass seed over an existing lawn. Done right, it's a straightforward process that gets results. As grasses mature, thinning is normal—especially if you enjoy your lawn and use it often. Overseeding keeps your lawn competitive and steeped in youth and vigor, without starting over from scratch.
The basics of overseeding are the same everywhere, but goals and timing vary based on geography and the type of grass grown. For success with overseeding your lawn, follow this basic guide:
- Establish Your Goal
- Time The Task
- Prepare The Area
- Correct Existing Problems
- Select A Quality Grass Seed Product
- Spread Your Seed
- Fertilize Overseeded Areas
- Keep Your Lawn Well-Watered
- Return to Regular Maintenance
Homeowners overseed to correct thin lawns, but pros overseed to prevent thinning. For lawns in southern regions, overseeding warm-season grasses with cool-season reinforcements adds green color during winter. When warm-season grasses go brown, overseeding with a premium, cool-season ryegrass, such as Pennington Annual Ryegrass, provides a green temporary lawn while your permanent, warm-season grasses are dormant.
The best time for planting cool-season grasses in northern regions is late summer to early fall, when they're growing most vigorously. Spring is the second best time. The warm soil encourages seed germination, cool fall air stimulates growth, and soil moisture stays more constant. Tough, warm-season lawn weeds, such as crabgrass and nutsedge, are less active in fall, too. The Turfgrass Water Conservation Alliance service recommends overseeding at least 45 days before your average first fall frost.1 In southern areas, overseed thinning lawns in late spring, as warm-season grasses enter active growth. For winter color, overseed southern lawns in fall. Wait until nighttime temperatures drop consistently below 65°F and your existing warm-season lawn slows and begins to lose color.
Mow your lawn extra short and remove the clippings, so new seed contacts soil and gets sunlight and water. Set your mower at two inches or less for regular overseeding. For southern lawns and winter color, set the blade as low as it goes, and cut just above the soil—what's known as scalping. Rake the soil with a metal thatch rake to remove thatch, clippings and debris. This loosens and exposes soil to receive seed.
For troubles beyond normal thinning, test your soil and make corrections before overseeding. Follow test recommendations for using soil amendments and repairing bare lawn spots. If needed, take time to dethatch and core aerate compacted lawns so air, moisture and seed can get to the soil. Pennington One Step Complete products combine premium seed with a stabilized-release fertilizer and wood mulch to simplify lawn repairs.
Better seed yields better lawns. Always use grasses recommended for your regional climate and choose top-quality grass seed you can depend on. Pennington Smart Seed products provide premium grass seed appropriate for sun, shade or high-traffic areas in lawns in northern or southern regions. Three-in-one Pennington Lawn Booster combines superior Smart Seed varieties with premium-grade fertilizer and soil enhancer.
Apply seed at label-recommended overseeding rates, using the lawn spreader that suits the job. Use drop or broadcast spreaders for large lawns and handheld spreaders for smaller areas. For small spots, simply seed from your hand. Work when the air is calm, so seed distributes evenly.
Avoid weed & feed products; the pre-emergent herbicides inhibit seed germination. Starter fertilizer, such as Pennington Ultragreen Starter Fertilizer 12-22-8, delivers essential nutrients for new grass. Phosphorus supports vigorous root growth, while nitrogen fuels top growth and greening. Some states and counties restrict phosphorus lawn fertilizers due to environmental concerns regarding runoff, but exceptions may be made for new seedings. Check with your local county extension agent about nutrient application restrictions.
Newly overseeded lawns need consistent moisture. Keep seed and soil moist with frequent, light waterings twice a day for the first four days; water more heavily every other day for the next five days; then water as needed to prevent wilting. This encourages deep, healthy roots.
Keep your newly revived lawn looking its best with a regular, comprehensive maintenance plan that includes diligent watering, best mowing practices and proactive overseeding. A simple weekday lawn maintenance schedule can keep your lawn lush and your weekends free.
For a simple, all-in-one approach to a thicker lawn, you can put your lawn on the fast track with Pennington Lawn Booster. This easy-to-use product simplifies overseeding to give your lawn the boost it needs. In just one application, your lawn will grow quicker, thicker and greener than ordinary grass—guaranteed.
Available in formulas for sun & shade or tall fescue lawns, Lawn Booster combines three essentials: seed, fertilizer and soil enhancer. Lime-enhanced, pure-bred Pennington Smart Seed, backed by years of breeding and research, adds beauty and sustainability. Once established, these water-conserving grasses require up to 30 percent less water than ordinary grasses. That's year after year, for the life of your lawn. Plus, they stay green up to three weeks without watering. That means less work and more leisure time for you.
The premium fertilizer in Lawn Booster stabilizes nitrogen in the soil, to reduce leaching and other nitrogen loss to the environment. Your seed gets nitrogen for immediate feeding and for extended feeding for up to eight weeks, without extra fertilizer inputs on your part. Moreover, the soil-enhancing gypsum in Lawn Booster corrects soil conditions to allow for better root growth, so your newly boosted lawn can flourish and be the talk of the neighborhood.
For the lawn of your dreams, don't wait to overseed until your lawn looks less than its best. Give your lawn the boost it needs, step-by-step or all-in-one. Pennington's here with premium grass seed and lawn care products to help you keep your lawn at its peak.
Pennington, One Step Complete, Smart Seed, and Ultragreen are trademarks of Pennington Seed, Inc.
Turfgrass Water Conservation Alliance is a registered trademark of NexGen Turf Research, LLC.
1. Turfgrass Water Conservation Alliance ; "Simple Tips," October 2014