01:00 AM EDT on Sunday, August 1, 2004

BY DENISE FLAIM
Newsday

Yellow spots on the lawn. "Kitty skittles" amid the summer squash.

If you have a dog or a cat, you know that sharing a garden with your pet has its special challenges.

"It's a matter of compromise and trying to come up with original ideas," says Cheryl S. Smith, whose new book, Dog Friendly Gardens, Garden Friendly Dogs (Dogwise, $19.95), offers solutions for everything from relentless tunnelers (create a "digging pit") to camouflaging an outdoor run (use black chain link, which fades into the background, and cover it with perennial vines such as honeysuckle).

Unfortunately, some problems just come with the territory, and trying to eliminate them is about as hopeless as growing roses in deep shade. A prime example are those yellow lawn patches that crop up wherever Fido takes a potty break. (Be sure, however, that you're not confusing them with "fairy ring," a fungus-based disease that can look similar.)

The reason for those unsightly spots is the urine's high nitrogen content, which will burn grass. So the best solution, says Smith, is to douse the affected area with water. "It doesn't have to be immediate," she adds. "Several hours afterward is just as good."

For those who don't have the time or inclination to follow their animals that carefully, prevention is best. "It's no harder to train your dog to potty in a specific area than it is to housebreak your dog to begin with," Smith says.

You want the designated area to be accessible to the dog, but a good distance away from areas where you dine and lounge. Consider shielding it with lattice or evergreen plantings such as rhododendrons, and providing a variety of surfaces -- say, half wood chips and half grass.

Male dogs who prefer to leg-lift on your favorite forsythia instead of squatting on the lawn present their own challenges. Despite being neutered, one of Smith's dogs is an inveterate marker, and she solved the problem with container plantings, "so he waters the pot and not the plant."

Owners of puppies, not to mention exuberant adults, are familiar with the divot-dotted landscape left in the wake of the occasional "frap." (For the uninitiated, that's short for "frantic rapid activity period" -- also known as "running around like a lunatic.")

Alas, there is no cure. "Even the master gardeners say, if you have a small yard and a big dog, give up," Smith shrugs. "It's just too much activity." The solution? Mulch.

Feline forays into the garden can be frustrating, too. The old-fashioned solution to stop cats from digging and defecating in your flower beds and vegetable garden is to cover the ground with chicken wire or a similar mesh covering. Other folksy deterrents include leaving lemon or orange peels in the area, with the hopes that cats will avoid the citrus smell.

But a new horticultural offering may hold some promise. Scaredy-Cat coleus (Coleus canina x Plectranthus) has a scent that is unpleasant to both cats and dogs. (Humans are oblivious unless they crush the leaves.) This drought-tolerant annual is now available here. (One source is www.gardeners.com, or call 888-833-1412.)

Another deterrent to unwanted kitty callers are sprinkler-system repellers such as the Scarecrow (available from www.frontgate.com, or call 888-263-9850). Attached to a garden hose and triggered by motion and heat, the unit discourages intruders with a three-second jet of water. "It works well on cats, and it's pretty good on squirrels, too, by the way," Smith says. "But a lot of water-loving dogs think it's great fun."

In the end, if you can't beat 'em, join 'em: Designate a cat-friendly area and fill it with plants that felines find irresistible, such as catmint.

Finally, remember that many plants are toxic to animals, including such garden staples as foxglove and lupine. And lay off the pesticides and insecticides: In a recent study from Purdue University in West Lafayette, Ind., Scottish terriers exposed to lawn chemicals were four to seven times more likely to develop bladder cancer.