How to Overseed a Lawn: 3 Benefits of Overseeding

Overseeding is the process of spreading seeds on an existing lawn to make it thicker and greener. With the help of a handheld rotary spreader, homeowners can spread grass seed over their thinning, yellowed lawn or dead grass to bring it back to life and fill in bare spots. Overseeding works on most lawn types, including fine and tall fescue, annual and perennial ryegrass, and Kentucky bluegrass. Overseeding yields the look of consistent and verdant grass on golf courses, and you can apply that same process on a smaller scale to make your home's yard bright and full.

Overseeding allows for a healthy lawn and comes with a host of landscaping benefits:

1. 1. Overseeding can help barren areas regrow. Lawns will naturally thin or yellow—dog pee, too much sun, and outdoor furniture can all affect the health of a lawn. When you overseed your lawn, you help stimulate root growth and fill in thinner areas.
2. 2. Overseeding can improve lawn density. Whether you have a new lawn or have been tending to yours for years, lawns can be prone to weed growth. Overseeding thickens the lawn density and makes it harder for weeds to take root.
3. 3. Overseeding can enhance color. Overseeding creates greener lawns and makes your lawn look more uniform. This process removes patchy areas and gives a front or back yard a full look.

Overseeding cool-season grasses can keep them verdant into the wintertime and prepare them for a strong regrowth come spring. These grasses, which grow in the northern US, can handle cooler weather and stay green in the fall. The best time to overseed is in the late summer or early fall. This helps with seed germination in the fall, instilling growth before the temperatures drop too low. Soil moisture is also better in the fall than it is in the winter. Come springtime, the young plants will have time to develop deeper roots thanks to the overseeding, and by summer, the grass will be green and full, eliminating competition from weeds like crabgrass and foxtails.

You should overseed warm-season grasses in the mid-fall. Warm-season grasses, like Bermuda grass or Zoysia in the southern US, are active in the spring and summer and go dormant come early fall. These grasses will resume growth when nighttime soil temperatures reach a minimum of 60 degrees Fahrenheit. Then, thanks to your overseeding, the grass will grow nice and full.

Homeowners can enact a few simple steps for a DIY overseeding process:

1. 1. Purchase your grass seed. You will want to buy seed that matches your turf type. Grass seed can be expensive, but the devices to spread them—rotary or drop spreaders—are affordable and won't take up too much space in your shed or garage. To maximize effect, you'll want to buy the right seed corresponding to your type of grass, disseminating the seed evenly (and perhaps more so in more barren areas).
2. 2. Mow your lawn. Fill up the lawn mower with gas, and mow your lawn down to about two inches, which might be shorter than you normally do. This will help the seed take root; if it sits too far up on the topsoil, it'll have a harder time getting into the ground. After seeding, wait at least three weeks before mowing again, so you don't tamper with the seeds' germination.
3. 3. Remove all the clippings. There will be grass bits and other natural foliage (leaves, branches) strewn about after you've mowed your lawn. Remove those so that you can have a clear seeding process.
4. 4. Rake or dethatch the grass. Rake the grass to loosen it up and enact soil contact with the seeds. If you have a large yard, you can use a pull-behind dethatcher. Place sandbags or weights on the dethatcher, so the metal tines scratch at least an eighth of an inch into the ground.
5. 5. Spread the seed. Fill up your broadcast spreader and consult the seeding package label for the seeding rate. Be sure to do this on a dry, still day. Too much wind can cast the seed off to areas you don't want it in.
6. 6. Fertilize to expedite growth. Spread a quarter of an inch of a starter fertilizer or compost over the seeded area of your existing grass to stimulate growth. You can do this with a shovel and wheelbarrow.
7. 7. Water consistently. Water your overseeded lawn twice a day for the first week; new seeds will require a lot of food to grow. In the second week, water in even greater quantities twice a day, and after that, you can water as needed and watch your new grass grow.

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