Dog urine is killing my lawn and even some of my garden. What do I do about it?
The best way to deal with this problem is also the most obvious: keep your dog from urinating on any part of your yard that you want to look nice. You can put in a fence, install a motion-activated sprinkler or lace your garden with repellent (not to be used near any edible plants) in the hopes that Fido will eventually clue in that there are spots in the yard where she cannot go.
I say 'she' for a reason. The problem is far more prevalent with female dogs who tend to empty their bladders in one spot than with males who mark their territories by spraying smaller amounts of urine in different areas – or so I'm told. I can't say I've ever made comprehensive study of when or how dogs urinate.
At any rate, when grass or garden plants start to die as a result of dog urine, the problem is primarily due to nitrogen toxicity. If you've ever dumped too much fertilizer on your lawn, you will have noticed that the burns caused by dog urine and those caused by excessive amounts of lawn fertilizer are essentially the same. There is a lot of nitrogen in dog urine and as little as one ounce is all it takes to produce negative effects.
Contrary to popular belief, studies have shown that dog urine doesn't dramatically change the pH level of the soil, so adding lime in response to dog urine won't neutralize the problem although it will inevitably alter the pH of your soil, which may or may not be a good thing.
Fortunately, nitrogen readily leaches from the soil, so the best way to reverse the effects of nitrogen toxicity is to flush the affected area with water. It doesn't take much. The ratio of water to urine needs to be a minimum of 3:1 in order to dilute the nitrogen to a level where it is no longer toxic. As long as you flush the affected area within eight hours of urination, you should be fine.
If you have any questions or comments, please send them to me at vanessa@gardenmuse.ca.
