How long does it take for dog urine spots to go away?

It depends on the damage and your grass. Purdue says the brown-and-green pattern can last several weeks, depending on how vigorous the surrounding turf is. Kentucky bluegrass spreads and can fill small spots, while NC State says tall fescue won't fill in dead spots on its own and needs seed, plugs or sod. Fully dead patches need reseeding.

Does baking soda fix dog pee spots?

No. Colorado State University Extension says baking soda and gypsum are salts and may compound the problem, and that water is the only thing that neutralizes urine's effects on grass. Soak the spot right after your dog goes, rake out anything that died, and reseed the patch in late summer or spring.

Can I give my dog a supplement to stop lawn burn?

Not without your veterinarian's OK. NC State Extension says supplements marketed for urine spots, including Methio-Form, ascorbic acid and potassium citrate, have no scientific merit and may harm your dog, and Colorado State says none has been proven to reduce dog spots. Watering the spot and training a potty area work without the risk.

When should I reseed dog spots in Michigan?

MSU Extension says Aug. 15 to Sept. 15 is the ideal seeding window in Michigan, when warm days and cool nights help seed sprout. Spring is the second choice, from late spring to no later than June 15. Keep the seed moist with light, frequent sprinkling, and keep your dog off the patch until it fills in.

Why does my lawn have dark green patches instead of brown ones?

Those can be urine spots too. Purdue notes that dog urine doesn't always kill grass. It can simply leave patches of darker, more vigorous turf, because grass responds quickly to the nitrogen in urine. The greening shows most on underfed lawns and when grass isn't actively growing, in early spring, midsummer and late fall.

Dog Urine Spots on the Lawn: Causes, Fixes

Turf specialists at Purdue and the University of Illinois call pets, especially dogs, the most frequent cause of dark green and brown patches in home lawns. The good news: the cause is well understood, and most of the fixes are cheap. Here's what's happening under those spots and how to bring the grass back.

Why does dog pee kill grass?

Because it lands as a concentrated dose in one small spot. A little nitrogen feeds a lawn. A whole bladder's worth at once, salts and all, burns it, much like a fertilizer spill.

Colorado State University Extension traces dog spots to a high concentration of nitrogen-containing compounds and associated salts landing on a small area, and Purdue compares the damage to a spilled salt-based fertilizer. NC State Extension adds a newer wrinkle: recent research has identified lactic acid in urine as the main culprit behind the dead grass.

Conditions make it worse. Purdue says damage is most severe when the soil is dry and the grass is poorly hydrated, and in hot, dry weather grass can die within 24 hours. The cool-season grasses common in Michigan lawns, such as Kentucky bluegrass, ryegrass and fescues (MSU Extension), take it hardest in a hot, dry spell.

And no, the nitrogen in dog waste doesn't make it lawn food. Here's why dog poop isn't fertilizer.

Why is there a dark green ring around the spot?

It's the same nitrogen, acting like fertilizer. Purdue describes the classic spot as a brown crater 3 to 6 inches across inside a dark green ring 6 to 12 inches across. The green-up shows most on underfed lawns, and in early spring, midsummer and late fall, when cool-season grass isn't actively growing.

Is it dog urine or a lawn disease?

Check the edge. Purdue lists dollar spot, summer patch and necrotic ring spot as look-alikes, but urine spots nearly always keep a lush, dark green rim that's still growing, and there's no cottony fungal growth on them in the early morning. Washington State University adds that urine-damaged grass gives off an ammonia smell.

Is female dog pee worse for grass?

No. Female dogs get the blame because they squat and empty their bladders in one spot. The urine itself isn't the difference. Here's how the common beliefs hold up.

Belief	What extension research says
Female dogs have stronger urine	Purdue points to squatting rather than chemistry, and notes that puppies of both sexes squat until they're about a year old. Colorado State adds that some males squat too, especially in their own yard.
The urine's pH burns the grass	Colorado State says dog spots don't happen because a dog's urine is alkaline, and Purdue notes that neither urine pH nor hormones has been proven to play a role.
Baking soda or gypsum neutralizes it	Colorado State says both are salts and may compound the problem, and that water is the only thing that neutralizes urine.
Tomato juice or a supplement will fix it	NC State says supplements sold for this, fruit juices included, have no scientific merit and may harm your dog.
Big dogs do more damage	True. Larger dogs release more urine, so their spots tend to be worse, per NC State and Colorado State.

How do you fix dog urine spots in the lawn?

Flush the salts, clear out the dead grass and reseed at the right time. Small spots in a bluegrass lawn may fill in on their own.

Soak the spot. Colorado State says to water brown spots more, or more often, to flush out salts that have built up in the soil.
Give it a few weeks. Purdue says spots can last several weeks, depending on how vigorous the surrounding grass is. Kentucky bluegrass, Michigan's most popular lawn grass, spreads by underground stems and recovers from injury quickly, according to MSU Extension.
Clear the dead patch. Rake out the dead grass, and loosen the soil underneath. An MSU Extension answer suggests adding topsoil before you reseed and watering it in well.
Reseed to match. Use the table below to pick seed. The same MSU Extension answer points to a "repair of dog urine spots" option in MSU's home soil test, which recommends amendments for the patch.
Keep the seed moist. MSU Extension's advice is light, frequent sprinkling that keeps the topsoil damp without leaving puddles.
Time it. In Michigan, MSU Extension's ideal seeding window is Aug. 15 to Sept. 15, when warm days and cool nights favor germination. Spring is second, no later than June 15.
Fence it off. Keep your dog, and everyone else, off the patch until the new grass fills in.

Got a big dead area, or no patience for seed? Sod is the faster route. Colorado State's repair is to lift the dead sod with half an inch to an inch of soil and lay new sod, and NC State lists plugging or sodding as options for tall fescue lawns.

Patching after the snow melts? The thaw is also when a winter's worth of piles shows up, so pair the repair with our spring cleanup guide.

Which grass is most tolerant of dog urine?

Tall fescue, among the cool-season grasses that grow here. Kentucky bluegrass tolerates urine the least, but it spreads to repair itself.

The University of Minnesota and NC State rank cool-season grasses the same way for urine tolerance. The growth habits come from MSU Extension, and the patching advice from Colorado State and Washington State.

Grass	Urine tolerance	How it grows	Patch with
Tall fescue	Highest	Bunch-type; NC State says it won't fill in dead spots on its own	Turf-type tall fescue seed
Creeping red fescue	Second	Spreads by rhizomes	Fine fescue seed only
Perennial ryegrass	Third	Bunch-type; sprouts faster than other lawn grasses	A seed mix that matches your lawn
Kentucky bluegrass	Lowest	Spreads by rhizomes and recovers quickly	Perennial ryegrass (more effective) or bluegrass

Growth habit is why the repair differs. Grasses that spread by rhizomes, like Kentucky bluegrass, can creep back into a small dead spot. Bunch-type grasses don't spread that way, and NC State says tall fescue won't fill in a dead spot on its own, so plan to seed it.

Renovating the whole lawn? The University of Minnesota suggests turf-type tall fescue mixed with Dutch white clover for a tough, low-maintenance lawn that kids and dogs can share.

How do you stop dog pee from killing the grass?

Water right after, give your dog its own spot, and keep the lawn strong.

Water it down. Kansas State University's turf team says to irrigate the spot with a watering can immediately. NC State says high volumes of water right after urination limit dieback, though the green ring may still show.
Make a potty zone. Colorado State calls training your dog to use a mulch or gravel area the only sure solution. NC State suggests mulched areas or the edge of the lawn, and a UC Davis housetraining handout says to take your pup to the same spot every time and praise it there.
Mow high. Purdue recommends 2 to 3 inches for most lawns, plus deep, infrequent watering during droughts.
Go easy on nitrogen. Purdue says a modest feeding can help blend green rings in, but fertilize only when the lawn can use it, not when it's dormant.
Keep the water bowl full. Colorado State says drinking more water dilutes urine and lowers the risk of lawn damage.

Do supplements or lawn products stop urine spots?

None has been proven to, and some can hurt your dog. Talk to your veterinarian before changing your dog's diet.

Colorado State says no dietary supplement has been scientifically proven to reduce dog spots, and it warns that supplements that add salt can cause problems for older dogs and dogs with heart or kidney conditions. NC State lists Methio-Form, ascorbic acid, fruit juices, baking soda and potassium citrate among the supplements with no scientific merit. Purdue adds that most of these products just make a dog drink more and pee more often, and that repellent products haven't been proven to keep dogs off a spot either.

If your dog suddenly pees more, less or in odd places, that's a question for your vet, not your lawn.

Spots often come with a smell. Our guide to getting rid of dog poop and pee smell covers rinsing, enzyme cleaners and what to skip. And our deodorize and sanitize add-on treats your dog's potty zones with a pet-safe enzyme spray for $8 a visit. Add it to any plan when you get your price.

Dog urine spots on your lawn: why they happen and how to help the grass