Overseeding your grass revitalizes your lawn. It fills in bare patches, improves the color and density, and makes the lawn more resistant to pests and disease. When done right, reseeding can dramatically improve the health and beauty of your lawn without the expense of starting over with sod. So, let’s see how to overseed a lawn for superior results.
Benefits of Overseeding
Overseeding is the process of planting fresh grass seed directly over existing turf. Rather than tearing out your existing lawn, the new seeds root right alongside your growing grass, filling in bare spots with new growth.
Did you know the average blade of grass only lives for a month or two? Its reproduction rate slows as the plant ages. Without overseeding, your lush green lawn will become sparse and lackluster. Overseeding is simple and effective, keeping your lawn young and resilient.
Further, overseeding is an easy way for homeowners to improve thickness and enhance a lawn’s color and resiliency by introducing and establishing more tolerant grass varieties. Overseeding makes your lawn more dense and lush. The thicker lawn becomes more tolerant of drought conditions and is naturally more resistant to weeds, diseases, and even insects.
Timing and Preparation
The best time for reseeding your lawn depends upon the type of grass you grow. Cool-season grasses like Kentucky Bluegrass, Fescue, Bentgrass, and Perennial Ryegrass are typically grown in northern gardens. They grow fast in spring and fall but not much in summer and then go dormant in winter. The ideal time to overseed a cool-season lawn is in the early fall when the temperatures spur quick germination and vigorous growth.
For warm-season grasses planted in the south, like Zoysia, Bermuda, St. Augustine, and Bahiagrass, overseeding in late spring to summer is best.
Critical overseeding tip: To optimize seed generation, grass seeds must come in direct contact with the soil. For this reason, aerating your soil before overseeding maximizes your results. Breaking up compacted soil and improving the ability for seeds, oxygen, nutrients, and water to reach the root zone makes overseeding far more effective.
To prepare your lawn for overseeding, start by weeding thoroughly, then mowing. Set your mower or tractor to its lowest setting, and be sure to bag your clippings. We don’t normally recommend giving your grass a buzz cut, but in this case, it helps the seed reach the soil. Once your lawn is mown, use a garden rake to loosen the soil and remove any debris.
Critical overseeding tip: After aerating, mowing short, and raking the lawn, water it well shortly before sowing the seed. This helps to keep the seed in contact with the soil and gives it the first moisture needed for germination.
Grass Seed Selection
Learning how to overseed the lawn requires choosing the right grass seed for your growing conditions. Consider your local climate first; cool-season grasses are ideal for northern areas, while warm-season grasses thrive in the south. Match the seed type to your existing turf to ensure compatibility and uniform growth.
Also, consider your lawn’s sun exposure. While most grasses thrive in full sun, some are more tolerant of shade. These include St. Augustine grass, Zoysia, and Perennial Ryegrass.
Soil type can also influence your seed choice; some grasses do well in sandy soils, while others prefer clay. For sandy soil, Bermuda grass, Zoysia, and Bahia are stellar performers. If your soil is heavy clay, Tall Fescue, Kentucky Bluegrass, and Ryegrass are good choices.
Seed Sowing Techniques
Once you have prepared your grass, there are a few options for how to overseed the lawn:
Broadcast Seeding:
The simplest method is broadcast seeding, whereby you spread seed over the ground by hand or using a hand-held rotary or drop seed spreader. Hand sowing is best for thickening up small patches of sparse grass. Scale up by using a rotary spreader for large swaths or an entire lawn. Thorough lawn prep is essential for broadcast seeding.
Slit Seeding:
This overseeding method uses a machine called a slit seeder which cuts grooves into the soil while simultaneously depositing seeds into the cut slits. This ensures excellent contact between the seeds and the soil, cutting through layers of thatch and roots. Slit seeding is ideal for lawns with severe thinning or extensive thatch buildup.
Seed Application and Fertilizer
A critical component of how to overseed the lawn is the seeding rate. Seeding rates vary depending on the grass species and whether you are overseeding an existing lawn or planting a new one. For example, Kentucky Bluegrass is sown at two to three pounds per 1,000 square feet for new lawns and one to two pounds per 1,000 square feet for overseeding. For Zoysia, overseeding with one pound per 1,000 square feet is ideal. Check the seed package for the appropriate seeding rate. If you have large bare patches, increase the overseeding rate a bit.
It’s important to avoid over-seeding, which wastes seed and leads to overcrowding, yet under-seeding will not give you the full, lush look you want. For uniform coverage, a broadcast spreader or drop spreader is ideal. Divide your total seed quantity in half. Walking at a steady pace, spread half the seed walking in one direction (e.g., north to south) and the other half at a right angle to the first direction (e.g., east to west).
Watering and Maintenance
Initial care is crucial for maximum effect. Once the seed is sown, water well to ensure good contact between the seed and soil and keep them moist. For the first few weeks, you want to prevent the soil from drying out without causing puddles. If you don’t get rain, plan to water as often as two to four times daily for the first couple of weeks. After that, gradually reduce the watering frequency while increasing the duration. Once your seeds have germinated, deeper watering will promote deeper root development.
Remember to start watering in the early mornings, and do not water at night. Redirect foot traffic around the lawn for the first month. Once the grass has reached your preferred height, you can resume regular mowing. Remember to abide by the one-third rule of mowing. You can resume fertilizing four to six weeks following the overseeding and establish a watering schedule.
Avoid Common Mistakes When Overseeding
The most common (and costly) mistakes come from a lack of preparation, skipping steps, or rushing the process. Follow each step in this guide to how to overseed the lawn.
Work with the proper equipment and supplies:
You need the right equipment to overseed your lawn well. Don’t try to broadcast spread seeds by hand for an entire lawn — you won’t like the results.
Avoid overseeding in the wrong season:
Timing is crucial to overseeding the lawn. Figure out the best seed for your growing conditions, and time it properly — early fall for cool-season grasses and late spring or early summer for warm-season grasses.
Don’t skip the lawn prep:
Aerating, raking, and “scalping” the lawn before overseeding are separate and crucial steps that ensure excellent results.
Mind the moisture:
Don’t overseed a dry lawn; give it a good drink before spreading the seed. Then, follow up with appropriate watering every day for the first few weeks, as described above. Don’t over-water — if you see puddles forming, stop and let them dry before watering again. You’re aiming to keep the surface of the soil evenly damp, not wet.
Don’t mow too soon:
Let the grass grow a bit longer than usual before your first mowing following overseeding. The faster-growing, mature grass blades protect the fresh new sprouts until they are ready to stand up to full sun on their own.
Hold off on the herbicides:
Using an herbicide too soon risks burning tender new roots and shoots. Wait for four to five mows before using an herbicide, weeding manually in the meantime.
Most Importantly, Call the Experts
Learning how to overseed a lawn is relatively simple and straightforward, but putting it into practice takes patience, commitment, and a keen eye. If you need help, contact the pros at Lawn Pride®. We are happy to help you achieve the most effective outcome. We can advise or dig right in to handle the lawn care service for you.
We know you’ll be pleased with our work because the Neighborly Done Right PromiseTM backs everything we do. Our passionate pros love your lawn almost as much as you do, and our results speak for themselves. Call us today for a free estimate.