How to stop dog urine killing your grass

Brown patches with bright green edges are a familiar sight for dog owners with lawns. The damage is natural and harmless to your dog, and it can be reduced with a few simple habits.

Why does dog urine kill grass?

Dog urine contains nitrogen from the normal breakdown of protein, along with salts. When a dog pees in one spot, it delivers a concentrated dose that scorches the grass, much like spilling lawn fertiliser. The grass around the edge gets a smaller, diluted dose, which acts as a feed and turns it extra green. That is why patches often have a dark green ring.

PDSA points out that a common misconception is that the damage is caused by the urine's acidity. It isn't.

Why female dogs cause more patches

The RHS notes that urine from female dogs is particularly likely to damage grass. This is because females usually squat and empty their bladder in one place, while males often lift a leg and spread smaller amounts against upright objects.

How to prevent urine damage

Water the spot straight away

Pour a watering can of water over the spot as soon as your dog has finished, or give it a good spray with the hose. This dilutes the urine and washes it into the soil before it scorches the grass. It is the single most effective fix.

Create a toilet area

Train your dog to use a particular part of the garden, such as an area of gravel or bark. Take your dog to the spot on a lead at toilet times and reward them when they go there. Choose a surface that is comfortable for paws.

Keep your dog well hydrated

Make sure your dog always has clean, fresh water. A well-hydrated dog produces more dilute urine. PDSA suggests adding water to meals or feeding a wet food to increase water intake. Your dog may then need to pee more often. Talk to your vet before making big changes to your dog's diet.

Look after your lawn

A healthy, regularly watered lawn copes better with urine and recovers faster. If you feed your lawn, use a pet-safe product, follow the dose instructions and keep your dog off the grass for as long as the label says.

Keep other animals out

Other dogs and foxes can also cause patches. Check your boundary for gaps.

Products and supplements to avoid

PDSA advises against giving your dog anything that changes the natural pH of their urine. It doesn't help with brown patches, and it could cause infections or bladder stones. Some products, such as stones placed in the water bowl, claim to work without changing pH. If you are considering one, research it carefully and speak to your vet first.

How to repair dead patches

Dead patches won't recover on their own, but they are easy to fix. The RHS recommends repairing lawns in spring or autumn, when the weather is cool and damp.

1. Rake out the dead grass and loosen the soil underneath.
2. Water the area well to wash out any remaining salts.
3. Sow grass seed that matches your lawn, or cut in a piece of turf from a less visible part of the garden.
4. Keep the patch watered until the new grass is established, and keep your dog off it if you can.