Ron is frantic. His urban cat has a perfectly good litter box but prefers to use the pots and planters on the sunny windowsill where Ron is trying to grow herbs. It’s only natural that his pet should prefer natural earth to the bagged imitation. Cats’ natural instinct is to bury their droppings in soil by digging and scratching it and the job’s much easier in soil that is loose and fluffy. The kind gardeners create.
Solving Ron’s problem is easy. Covering the soil with attractive stones, or a lid of chicken wire cut to accommodate the plant’s stem, will send Kitty back to her box. Even cats that nibble on or play with foliage can be foiled by a hanging planter (unless they’re trying out for a feline Cirque de Soleil). But for outdoor gardeners the problem is a more serious one. Cat and dog excrement contains pathogens that are transmissible to humans and it’s especially important to keep their poop out of food gardens.
Soil barriers work outdoors too, especially in a small garden. Strips of wire mesh placed between plant rows and removable for cultivating and weeding are effective, as are flagstones, bird netting, pieces of carpet, black plastic, or any agricultural fabric such as Reemay or shade cloth. When mature, crops such as kale and squash will block access with their large leaves. Cats avoid a garden strewn with rose or raspberry briers, though you might too, unless you wear leather gloves. Some people swear by repellents applied to the soil. I’d avoid any commercial product with a warning label on it, but a five-alarm dressing of hot pepper, curry powder, mustard, garlic, chopped citrus peels or eucalyptus oil might help. You’ll need to whip up a fresh batch whenever it rains. Plants such as rue or Coleus canina are said to have an effect.
With any repellent you might have to provide another place for the cat to go. After all, even a restroom that reeks of cheap potpourri — or worse — will be used if there is no nicer one nearby. Some people set aside an area with loose soil or peat moss and maintain it as a litter box. As a lure, they plant a cat grass such as oats or catnip, which is a cat narcotic. But I’m dubious. Most creatures prefer not to do their business where they eat or do drugs.
Your best trump card is the fact that cats hate water. A squirt gun is a handy item for the tool basket, a hose even better. (For times you’re not there, you can use a motion-sensing animal-squirter.) According to Shannon Hayes, author of “The Grass Fed Gourmet “and wise in the ways of the four-footed, the hose trick is foolproof. “It’s also deeply satisfying,” Shannon says.
Barbara Damrosch’s latest book is “The Four Season Farm Gardener’s Cookbook.”