A lush, green lawn can make your home look better from the street. But all lawns get patchy, thin, and overgrown with weeds over time. Overseeding is a simple and effective way to fill in bare spots, kill weeds, and make your lawn look more even again.
In this comprehensive guide we’ll cover everything you need to know about overseeding including
What is Overseeding?
When you overseed, you just add grass seed to your existing lawn without tilling or turning the soil. The grass seed blends in with the existing grass and makes it better. Overseeding improves color, thickness, and durability. It introduces hardier, upgraded grass varieties to the lawn.
Why Overseed Your Lawn?
There are several reasons you may want to overseed your lawn:
- Bare patches from pet urine, heavy foot traffic, drought damage, or disease
- Poor color from depleted nutrients or shade
- Thin turf from old age or improper mowing
- Weed infestation choking out the grass
Overseeding enhances the lawn’s appearance by filling in bare spots and thickening thin areas. It chokes out weeds by encouraging dense, vigorous grass growth. The newer grass varieties resist disease, insects, and environmental stress better than older types. Overall, overseeding restores your lawn to a lush, green, weed-free state.
When to Overseed Your Lawn
Timing is crucial for successful overseeding. When you spread out cool-season grasses like bluegrass, ryegrass, and fescue in late summer or early fall, they grow better. The soil is still warm, encouraging fast germination. But it’s cooler, which means that weeds that like it hot won’t be as strong of a competition. Cooler fall temperatures also reduce stress on young grass seedlings.
Warm-season grasses like bermuda, zoysia, and centipede do best when overseeded in early spring. The soil starts warming up, allowing for quick germination. The new grass has time to mature before the intense heat of summer returns.
If you overseed your grass type before the best time for it, it will probably not germinate or grow well. Talk to your local extension office to find out when the best time is to overseed in your area.
How to Overseed Your Lawn
Follow these steps for effective overseeding:
1. Mow, Dethatch, and Aerate
Mow your lawn shorter than normal to allow better seed-soil contact. Dethatch if the grass has heavy thatch buildup; this removes barriers between seeds and soil. Consider aerating, which creates seed beds in the soil, especially if it’s compacted.
2. Choose the Right Grass Seed
Select a seed variety suited to your region’s climate and compatible with your existing grass. Improved grass cultivars resist diseases, insects, drought, and other problems better than older types. Purchase quality seed from a reputable supplier.
3. Spread the Seed
Use a drop spreader or rotary broadcast spreader to distribute the seed evenly. Apply half the seed walking in one direction across the lawn, then apply the other half walking perpendicular to the first direction. Follow package directions for correct application rate.
4. Lightly Rake the Seed
Use a steel lawn rake to very lightly rake the grass seed into the top 1/4 inch of soil. This improves seed-soil contact for better germination. Take care not to rake deeply or you may bury the seeds too deeply.
5. Water, Feed, and Watch Growth
Water lightly but frequently after seeding to keep the top 1/2 inch of soil moist. Once sprouted, reduce watering frequency but water more deeply. Apply starter fertilizer to encourage vigorous growth. Let the new grass reach 3 inches tall before mowing. Gradually reduce watering frequency as the grass matures.
Tips for Overseeding Success
Follow these tips to ensure your overseeding project succeeds:
- Overseed at the right time of year for your grass type
- Mow, dethatch, and aerate before overseeding
- Select high-quality seed suited to your climate
- Use proper seeding techniques and rates
- Water new seeds frequently until established
- Let new grass reach 3 inches before mowing
- Fertilize according to grass type and time of year
- Avoid excessive foot traffic on newly overseeded areas
Overseeding requires some work up front but pays off with a thicker, greener, healthier lawn. Make overseeding an annual fall ritual for a perfect lawn every year. Let the lush curb appeal of your property make your neighbors green with envy!
Frequently Asked Questions about Overseeding
Many homeowners have questions about properly overseeding their lawns. Here are answers to some of the most common overseeding FAQs:
How much does overseeding cost?
The cost of overseeding depends on lawn size and materials needed. Budget $100-$200 or more for products to overseed an average 5,000 sq ft lawn. Costs include grass seed, fertilizer, dethatching/aerating services, and equipment rentals or purchases.
How long does overseeding take to fill in?
It takes 10-14 days for new grass seed to germinate and sprout. The lawn will show noticeable improvement within 3-4 weeks after overseeding. Full establishment takes about 2-3 months for cool-season grasses and 4-6 weeks for warm-season varieties. Proper watering reduces the fill-in time.
Can I mow right after overseeding?
It’s best to wait until the new grass reaches 3 inches tall before mowing. This allows the seedlings to develop deep roots and prevents them from getting scalped or uprooted by the mower. Letting the new grass get taller also creates more leaf surface area for growth.
Do I need to water newly overseeded areas?
Yes, frequent light watering is critical after overseeding to keep seeds and seedlings moist. Water 1-2 times daily until sprouted, then reduce frequency but increase depth. Gradually taper off watering as grass matures. Proper watering is key to fast germination and establishment after overseeding.
Should I fertilize after overseeding?
Yes, applying starter fertilizer after overseeding helps the tender young grass plants grow quickly. Look for products labeled as starter fertilizer or turf builder for new seedlings. Follow product directions to determine how and when to fertilize newly overseeded areas.
How often should overseeding be done?
Many homeowners overseed as needed to fill bare spots or once per year as routine lawn maintenance. Cool-season northern grasses are best overseeded in early fall. Warm-season southern grasses are best overseeded in early spring. Overseed outside optimal times for faster infill of damaged areas.
Overseeding is an easy, affordable way to thicken up patchy spots, choke out weeds, and improve the color and quality of your lawn. Follow the tips above for lush, thick, green grass that makes your neighbors green with envy!
How to Overseed a Lawn
Overseeding a lawn means planting grass seed directly into your existing grass. It helps prevent weeds from taking over your lawn and promotes healthier growth. One of the most important things to consider for overseeding is timing. Additionally, proper overseeding depends on the type of grass that grows best in your climate.
Of course, you can try sprinkling grass seed on your lawn. Simply adding grass seed to your lawn will result in poor seed germination. You will get best results when you follow to steps for overseeding a lawn.
Overseeding a lawn is best done in spring or fall, depending on the type of grass in your yard.
- Kentucky bluegrass, perennial ryegrass and fescue are cool season grasses. If you want to grow cool season grasses, it’s best to overseed your lawn in the fall. For starters, the soil is still warm enough for seeds to sprout, and the cool air helps grass grow strong roots. In the North, fall comes earlier, so it’s best to spread out cool season grass by late summer or early fall.
- Bermuda, Centipede, Saint Augustine and Zoysia are warm season grasses. In the South, the best time to spread warm-season grasses is in late spring or early summer. In the spring or early summer, make sure to water grass seedlings often and lightly. This will help them get set up before it gets hot and dry.
Overseeding a lawn takes planning and preparation. Youll need tools like a mower, a thatch rake, an aerator and spreader. Before you start:
- Figure out the size of your lawn. A measuring wheel can help. To find the square footage of your lawn, multiply its width by its length. If your lawn is spread out over more than one area, measure each one and add up the square footages.
- Before you overseed, don’t feed your lawn for at least a month. You can’t see the new seeds as well because the fertilizer makes the grass grow faster.
- Figure out what kind of grass you have or want to grow. That way you can manage it appropriately.
- Think about the weather where you want to grow grass, look at the shape of the blades of grass you already have, and feel the texture of the grass you already have.
A layer of thatch is made up of dead grass blades, stems, and roots mixed with living plant parts. A thick layer of thatch can lead to disease and insect problems if you dont remove it. It can also keep grass seeds from germinating.
- Cut your grass short enough so that it sits above the ground. The grass blades shouldn’t be more than 1 to 1 1/2 inches high. This will help the new grass seed get enough sun and reach the ground well.
- Get rid of any thatch you find with a dethatcher or power rake.
- To dethatch, rake your lawn in one direction. Give it another pass in the opposite direction. The rake’s tines will pick up the thatch as they go. Be sure to remove the thatch off the lawn.
Aerating your lawn loosens the soil so air and water can reach the roots. It also combs out your grass and kicks out debris. Aerating your lawn will help grass seed grow faster and better. Its especially important to aerate lawns that are compacted by heavy foot traffic.
To aerate a lawn, move a core aerator across the yard in straight lines. Cover the entire yard. Do a second pass perpendicular to the first one, if needed. The core aerator should pull up plugs of soil instead of just punching holes in the ground. This helps break up the compaction. Leave the plugs on the ground and theyll disintegrate in a couple of weeks.