Protecting Plants And Gardens From Deer And Rabbits

Late fall is the time to protect young trees and shrubs from deer and rabbits.

"While other animals may cause damage during the winter, these are the main culprits (in Pennsylvania)," says Dr. J. Robert Nuss, professor of ornamental horticulture in Penn State's College of Agricultural Sciences. "They can damage and kill plants that are expensive to replace."

Deer are browsers, preferring to nibble on the buds, twig-ends and leaves of woody plants. Browsing destroys new growth and deforms shrubs and trees. Extremely young plants may be eaten completely.

Unless you have a large number of young trees and shrubs to protect, the most economical and practical method is fencing individual plants. "Many homeowners enjoy seeing deer on their land and don't want to fence them out of the entire area," says Nuss. "Individual fencing allows deer in the garden but keeps them from causing mischief."

To fence a plant, drive three or four tall wooden stakes into the ground around it, about 48 inches from the trunk, or far enough away to prevent feeding in the lower branches. Attach woven wire or plastic mesh to these stakes to form a circular fence.

"Fencing must be high enough to protect all parts of the plant within deer's reach," says Nuss. "If the tree or shrub is under 3 feet tall, you will need to make the fence several feet taller than the plant."

Young trees and shrubs should be fenced every fall until their primary branches are about 5 feet high. "Inspect your fencing at least once a week," says Nuss. "After heavy snowfall, you may need to make it taller. Deer can walk across hardened snow and nibble on the tops of plants."

If you have many plants to protect, you can surround the entire area with woven-wire fence at least 8 feet tall or at least 11 feet tall if the land slopes and deer can jump from above. "This method is expensive but will keep out other destructive animals as well," says Nuss.

Chemical deer repellents are another alternative and can be bought from garden centers. A homemade repellant can be made from 6 spoiled eggs, 3 gallons of water and 3 tablespoons of 75 percent Thriam, a mild fungicide. "Plants sprayed with repellants taste and smell unpleasant to deer," says Nuss. "But they wash off in rain and snow, and won't deter extremely hungry deer."

If deer are a severe problem, consider planting trees and shrubs that naturally resist browsing. "No plant is completely deer-proof, but trees such as box elders, black locusts, pines and spruces resist deer damage," says Nuss. "Barberries, hollies, tree peonies, rhododendrons and lilacs are deer-resistant shrubs."

Rabbits can cause as much damage as deer, chewing the bark off young trees and shrubs. Rabbits can kill plants by girdling them -- gnawing off a ring of bark all the way around the trunks. "Fortunately, they're easier to control than deer because they can reach only to about 24 inches high," says Nuss.

A variety of rabbit-proof wrappings, available at garden centers, can be quickly and easily wound around plants' trunks. These wrappings are weatherproof but should be checked regularly to make sure they're still securely wound.

Individual fencing also is practical and inexpensive. "It can be constructed the same as deer fencing, except that the bottom of the fence must be buried 2 to 3 inches into the ground so rabbits can't tunnel underneath," says Nuss.

"Rabbit fencing should have holes no larger than 1 inch," says Nuss. "Stakes holding the fencing must be firmly planted and the mesh must be securely attached. Otherwise, rabbits can press against the mesh and nibble at the plant right through the holes."

Larger areas can be fenced the same way, with the bottom of the fence curled outward and buried 6 inches. "Whether you're using plastic wrapping, individual fencing or large-area fencing, make sure it's at least 24 inches tall," says Nuss. "If snow accumulates, the fencing must be 24 inches higher than the snow. Check larger fenced-in areas frequently. If a rabbit does get caught inside, it may not be able to escape."

Chemical repellents also will keep rabbits away from ornamental plants, but they must be reapplied frequently, especially after it has rained. Hungry rabbits competing for food will nibble plants even if they are treated with a repellant.

"With a little time and care, you can protect young ornamentals from deer and rabbits," says Nuss. "Of course, no method is 100 percent effective, and you may have a little damage each winter. As young trees and shrubs grow, the problem naturally will diminish."