Smaller than a fist
Wait
fills in on its own
Germination
2–3 wks
Iowa State Extension
Watering
Daily+
light, until it sprouts
A bare spot is the easiest lawn repair there is, and one that often gets done twice, because the seed goes down before anyone asks why the grass died. This guide starts with the cause, then covers reseeding, patching with sod and the watering that decides whether new seed takes. If the whole lawn is thin rather than spotted, you want overseeding instead.
What Killed the Grass?
University of Wisconsin–Madison Extension lists dog urine (its high nitrogen), damage from shovels and plows along walks and driveways, and turf left exposed when insulating snow was cleared as common causes of dead spots after winter. Grubs, shade and compaction cause the rest. Fix the cause, then the patch.
| Cause | Clue | Do first |
|---|---|---|
| Dog urine | Round dead spots where the dog goes, most visible in spring | Keep the dog off the spot until the new grass is mowing height |
| Snow plows and shovels | Scraped strips along walks and the driveway | Rake out the debris and gravel thrown onto the turf |
| Grubs | Turf that lifts like carpet; animals digging | Confirm and treat grubs before you seed |
| Shade | Thin, weak grass under trees that never fills in | Reseed with a shade-tolerant grass such as a fine fescue |
| Compaction and traffic | Worn paths, hard soil a screwdriver won't enter | Loosen or core aerate the soil |
To rule grubs in or out, use the pull test in the grub guide; for hard, compacted soil, see the aeration guide.
Repairing a Spot with Seed
- 1
Leave fist-sized spots alone
Wisconsin Extension says spots smaller than your fist usually fill in from the surrounding grass within a few weeks.
- 2
Clear the dead grass
Rake out enough dead blades that you can see soil. You don't have to remove all of it.
- 3
Loosen the surface
Scratch up the top of the soil with a hard rake so seed has somewhere to land.
- 4
Mix seed into soil
Wisconsin's method: stir a couple of handfuls of seed into soil or a bagged mix and spread it over the spot. Match the seed to the grass already growing.
- 5
Press for contact
Rake lightly, then press the area with your foot or the back of the rake. NC State calls seed-to-soil contact paramount.
- 6
Keep it moist
Iowa State recommends frequent, light watering, usually at least once a day; Wisconsin suggests misting daily if it doesn't rain.
Iowa State says to expect germination within 2 to 3 weeks; once the new grass reaches mowing height, mow it with the rest of the lawn. For more than a few patches, the grass seed calculator works out bags, and the full process is in how to plant grass seed.
How Much Seed You Need
Bare spots get the new-lawn seeding rate, not the lighter overseeding rate. NC State uses 5 to 6 pounds of uncoated tall fescue seed per 1,000 sq ft; your bag label gives the rate for other grasses. Most patches need ounces, not pounds.
Patch planner
Measure each bare spot (feet). Round irregular spots up to a rectangle.
- 1×6 sq ft
- 2×20 sq ft
Check your seed bag's new-lawn rate
Total bare area
26 sq ft
Seed needed
2.5 oz
Patching with Sod or Plugs
Sod is the faster fix for a visible spot by the front walk or for warm-season lawns that don't seed well. Cut the dead area into a clean square, loosen the soil, set the new piece so it sits level with the lawn around it, and water it daily until it roots. St. Augustinegrass can't be patched with seed at all; Texas A&M AgriLife Extension notes it is planted as sod, sprigs or plugs because seed is not available.
Not sure which way to go on a bigger area? Weigh it on sod vs. seed, and check whether the lawn is cool-season or warm-season before you buy anything.
Best Time to Patch
For cool-season lawns, late summer into early fall is the best window: Iowa State recommends mid-August to mid-September, and NC State calls fall the best time to seed cool-season lawns. Spring patches work too, as Wisconsin's spring repair method shows, but they have a shorter run before summer heat. Warm-season lawns repair best while the grass is actively growing in the warm months. Keep pre-emergent herbicide off any spot you plan to seed; the spring lawn care checklist explains the conflict.
Common Questions
Do all-in-one patch products work?
They can, on small spots: they combine seed, mulch and fertilizer in one bag. They still need the same prep (dead grass out, soil loosened) and the same daily watering, and the seed should match the grass already in the lawn.
How long before I can mow the patch?
Wait until the new grass reaches the normal mowing height for the lawn, and mow with a sharp blade so the young plants are cut, not pulled. Keep foot traffic and dogs off it until then.
Why did my patch fail?
The usual reasons are that the seed dried out between waterings, the seed never touched the soil, or the original cause (grubs, shade, a dog, a plow) is still there. Fix the cause and repeat in the next good seeding window.
Should I fertilize a new patch?
A starter fertilizer at seeding helps new roots, but keep weed-and-feed products with pre-emergent herbicide off the patch, since they stop grass seed from germinating too.