Short answer
Overseeding spreads fresh grass seed across an existing lawn to thicken it and fill thin areas. Late August through mid September is the best window in Illinois. Seed needs soil contact and steady moisture for two to three weeks, which is why we run it right behind core aeration.
Why lawns thin out on their own
Cool season grasses have a life span. Individual plants age out, summer heat takes some, traffic and pets take more, and disease clears patches in a humid August. A lawn that gets no new seed loses density every year even when you feed it, and every open spot is a landing pad for weed seed.
- Fills thin spots before weeds claim them
- Introduces newer grass varieties with better disease resistance
- Improves color and texture across the whole lawn
- Rebuilds shaded areas and traffic paths that thin every summer
- Lowers how much herbicide the lawn needs going forward
Overseeding is a separate seasonal service. It is recommended and priced on its own rather than included in the Essential, Enhanced or Elite programs. Compare the lawn programs
How overseeding works on our route
Seed is the cheap part. Contact and moisture are what decide whether you get a lawn or a bill.
Aerate first
Open holes are the seedbed. Seed broadcast on hard soil washes off, blows away or feeds the birds.
Match the seed
Sun, shade and traffic all call for different blends. We pick the mix for your property instead of running one bag across every lawn.
Broadcast the seed
Applied at the rate the lawn actually needs. Heavy is not better, since crowded seedlings compete with each other and thin themselves out.
Starter feeding
New seedlings need phosphorus at the root. A starter blend goes down with the seed.
Water daily for two weeks
Short, frequent watering keeps the seedbed damp. This is the step that decides the outcome, and it is on you between visits.
Hold off on weed control
Pre emergent blocks your new seed the same way it blocks crabgrass. We plan the herbicide schedule around the seeding date.
Spring seeding rarely works here
Grass seed sown in spring germinates into the worst conditions it will ever face. It gets six weeks of root growth before summer heat arrives, competes with crabgrass at its peak and cannot be protected by pre emergent without killing the seed too.
Fall reverses all three. Soil stays warm while air cools, weed pressure drops off and the seedling gets the whole fall plus the following spring to root before it faces heat. Same seed, same money, very different lawn.
- Seed blends matched to sun, shade and traffic
- Applied at rate right behind the aerator
- Starter fertilizer included with the seeding
- Watering schedule written out before we leave
Pairs well with
Lawn aeration
Aeration and overseeding are one job. Holes give the seed the soil contact it has to have.
See aerationFertilization
A starter feeding at seeding and a fall round after establishment carry the new grass through.
See fertilizationLawn restoration
Past a certain amount of bare ground, overseeding alone will not close the gap.
See lawn restorationOverseeding questions we get
Late August through mid September. Warm soil speeds germination, cool air reduces stress and the seedling gets the whole fall to root.
Perennial ryegrass shows in five to seven days. Fescue takes seven to fourteen. Bluegrass runs fourteen to twenty eight, so a blend comes in waves.
Light watering once or twice a day for two to three weeks, enough to keep the top half inch damp. Deep soaking every few days does not work for seed.
Not right away. Most herbicides need the new grass mowed three or four times first. We schedule the seeding and the herbicide so they do not collide.
You get far better results with it. Seed lying on compacted soil has almost no chance, which is why we run the two together.
It runs off square footage and the seed blend. Call (815) 521-6356 and we will price it with the aeration.
Thicken the lawn while the window is open
Fall seeding runs on a short calendar. Call and we will get you scheduled.
