Many gardeners have problems with neighbours’ cats using their vegetable patches and flowerbeds as litter boxes. There are effective strategies for keeping cats out of gardens that won’t harm people, animals, or the environment.

Water

Most cats hate to be squirted with water. Purchasing a squirt gun and squirting the invader a few times will usually do the trick. For those with a bit of money to spend, motion-sensing sprinkler systems are available. A motion-sensing sprinkler system will squirt any animal (or person) that moves in the area, so it may not be the best idea if the water can reach the front walk. Also, motion-sensing water sprinklers are not a viable solution in areas that suffer from water shortages.

Cat-Repelling Plants

Many people recommend planting rue because its strong scent repels cats, but rue can be toxic if ingested and can also cause unpleasant skin reactions in people. Planting lavender, lemon thyme, and coleus canina are safer options. A thick bed of prickly roses or some cacti around the perimeter of the yard or in the area where cats are getting through a fence can also be highly effective.

Landscaping Options

Cats love soft dirt. Covering dirt with rocks, shale mulch, or pine cones makes it far less appealing. Lining the perimeter with upside-down plastic carpet runner (pointy side up) can be quite effective, as cats don’t like to walk on the points. If there is one particular area the cat favours, planting a series of upright sticks in the soil will solve the problem.

Cat Fences

Cat fences are designed to keep cats in a yard, but they are equally effective at keeping cats out. They can be purchased either as freestanding fences with stakes that anchor them to the ground or as extensions that attach near the tops of fences to keep cats from climbing over. Chicken wire can also be used to form a barrier around the entire yard or specific areas that a cat is targeting.

Cat Repellents

There are commercially available non-toxic dog and cat repellent sprays. Good products are scent-free and environmentally friendly. Citrus fruit peels (lemon, orange, and grapefruit) and tea leaves are thought to be natural cat repellents, though not everyone has success with these.

A Resident Dog or Cat

An adopted pet can act as a security guard for the garden. If there is a resident dog or cat that has laid claim to the yard, it’s far less likely that neighbourhood cats will visit, and a resident cat can be trained not to use the garden as a toilet.

Sound Devices

Ultrasonic sound devices that run on batteries can be used to drive dogs and cats from the yard. These motion-activated devices emit sounds that animals hate but that are inaudible to humans.

Strategies to Avoid

There are a number of cat-repellent strategies that are commonly recommended but shouldn’t be used. For example, mothballs are toxic and although they are an effective pest repellent, they can be deadly for pets, local wildlife, and children who may pick them up and put them into their mouths. They will also repel beneficial insects such as ladybugs, which eat aphids and other garden pests.

Sprinkling hot pepper (black pepper, cayenne, etc.) is also a bad idea. Not only does the pepper have to be reapplied frequently, but there is the risk that animals will walk over it and then lick their paws or rub their eyes. Small children may also pick up the pepper on their hands and then put their hands in their mouths or touch their eyes.

Further Reading

For non-toxic, environmentally friendly ways to rid the garden of insect pests, see Natural Garden Pest Control.

References:

• Cat World. (2008). “Keeping Cats Out of Gardens.” Cat-World.com.au.
• David Suzuki Foundation. (2008). “Mothballs: They Smell Bad for a Reason.” DavidSuzuki.org.
• Perry, Leonard, Dr. (n.d.). “Keeping Cats out of the Garden.” University of Vermont Extension Department of Plant and Soil Science. UVM.edu.
• Russell, Alice B., Dr.; Hardin, James W.; Dr., Grand, Larry, Dr.; & Fraser, Angela, Dr. (1997). "Poisonous Plants of North Carolina." North Carolina State University. (1997). CES.NCSU.edu