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: 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 Perennial Ryegrass, provides a green temporary lawn while your permanent, warm-season grasses are dormant. The best time for overseeding 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 weeds, such as nutsedge and crabgrass, 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 clippings, thatch 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. 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. 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. Overseeding: A Quick Guide There are many little steps that homeowners can take as part of their regular lawn maintenance to ensure a vibrant and full lawn year-round, and one of the most important is overseeding. This is defined as the act of sowing seed throughout your existing lawn. Over the years grass takes longer and longer to grow, making it difficult to maintain a full lawn cover and allowing unwanted weeds to pop up. Overseeding can improve patchy dead spots in lawns and ensure a lush appearance. Overseeding can also be used to supplement your existing lawn during harsh months of the year. If you live in the southern part of the United States and have warm-season grass, then adding cold season grass during the cooler months on the calendar can lead to an extended growing season for your yard. The best times for overseeding are right after the summer from mid-late September into early October. If you miss that window, then the next best time is around the first signs of spring weather in your area. Replacing your whole lawn can be a tedious and costly endeavor. So adhering to the following overseeding process can save you time and money in the long run. The Overseeding Process 1. You must first prime the area for the new seeds. This can be done by mowing the grass to an even height of one to two inches, which provides the best setup for proper absorption. You should also aerate the tough patches of soil to allow for proper seed entry into the turf. Next, it’s best to lay a light layer of compost over the desired area to provide nutrients to the newly added grass seeds. It’s better to lay too little compost, rather than too much, so be conscious of how much you spread across the yard. 2. Before you proceed, be sure to do your research on the type of grass in your yard and the type that you will be adding. The only thing worse than patches of dead grass in your yard is two grass species with different colors and appearances clashing in your lawn. Once you pick the grass seeds you want to add to your lawn, spread the seeds evenly across the yard. You can use tools like a rotary spreader or a drop spreader, or just use your hands as long as it’s an even layer. After you complete that, gently rake the grass to make sure the seeds are properly incorporated with the dirt. 3. To complete the process, apply an extended time-release nitrogen fertilizer and water the area. Keep the new sod moist over few weeks until you begin to see sprouts. For the first couple of months it’s best to keep the grass at a height of 1 3/4 to 2 1/4 inches.
