You love your dog, but it's hard to love the urine damage she may cause to your plants. Even if you've trained your dog to relieve herself away from the garden areas in your yard, neighborhood dogs may not be so respectful of these boundaries. If an area is particularly attractive to dogs as their preferred "doggy bathroom," grow urine-resilient plants, which may be better able to withstand the damage from urination.
When dogs urinate on plants, the urine kills plant tissues by dehydrating plant cells. As water is pulled out of the dehydrating cells, this causes plants to turn yellow and then brown. If plants cannot recover from this loss of water, they die. Urine damage is not confined to a certain gender -- male and female dogs can cause problems. Male dogs, however, usually have a different urination posture and marking behavior stance -- they typically lift their legs instead of squatting as most females do. This means male dogs may cause more damage to ornamental plants than females do.
What Causes Damage
Dog urine burns plants because of uric acid, the primary component of dog urine. Although a high pH is often attributed as the cause of urine damage, the true culprits are the nitrogen and soluble salts concentrated in acidic urine. These caustic components are capable of delivering a fatal blow to some garden plants.
Saline soils -- those with a high concentration of soluble salts -- can dehydrate some plants by pulling water out of plant roots into the surrounding salty soil. Because dog urine also contains soluble salts, it causes similar damage to plants as saline soils. Salt-tolerant plants, such as daylily (Hemerocallis spp.), a perennial in U.S. Department of Agriculture plant hardiness zones 3 through 10, are also urine-tolerant.
Chinese snowball viburnum (Viburnum macrocephalum) -- USDA zones 6 through 9.
Japanese rose (Rosa rugosa) -- USDA zones 2 through 7.
Japanese spirea (Spiraea japonica) -- USDA zones 3 through 8.
New Zealand flax (Phormium tenax) -- USDA zones 9 through 11.
Feather reed grass (Calamagrostis x acutiflora 'Karl Foester') -- USDA zones 5 through 9.
Blue-lyme grass (Elymus arenarius aka Leymus arenarius) -- USDA zones 4 through 10.
Dutch white clover (Trifolium repens) -- USDA zones 4 through 8.
Plants with high nitrogen fertilizer needs may be more tolerant to dog urine damage.
How to Prevent or Mitigate Damage
- If you see your dog -- or a neighbor's -- urinating on plants, immediately flood the plants and the ground around them with water.
- Keep plants fertilized according to soil-test recommendations to keep them in optimal health.
- Train your dog to a certain "potty area" in your yard that's away from plants.
- Exclude neighborhood dogs by fencing them out of your yard or garden.
- Install a motion-activated sprinkler that aims a jet of water at unwelcome dogs.