As a general rule, ivy (Hedera spp.) isn't at the top of the dining list for deer, which often avoid plants with thick, leathery leaves. However, because hungry deer aren't choosy and will eat nearly anything, no plant is 100 percent safe. Although discouraging deer from eating ivy is extremely difficult, you can use a variety of tactics to discourage the unwanted visitors from munching your ivy vines. Ivy grows in U.S. Department of Agriculture plant hardiness zones 5 through 11, depending on the variety.
Repellents -- Taste
Liquid repellents made of various bad-tasting ingredients often prompt hungry deer to move on to more pleasant pickings. Experiment to determine which repellent works best, because effectiveness may vary depending on environmental conditions, location and time of year. Replace repellents after a rain, and switch repellents often to maintain effectiveness; deer soon become accustomed to the bad taste. Although a number of commercial repellents are available, you can mix your own homemade bad-tasting repellent consisting of water mixed with rotten eggs, hot peppers or deodorant soap.
Repellents -- Scent
Deer often turn up their noses at bad-smelling substances. As with taste repellents, you can purchase a variety of commercial products. However, you may have success with mesh bags filled with human hair or bars of strongly scented deodorant soap. Hang the bags on the outer ends of ivy stems and nearby tree branches, and replace the bags every month throughout spring and summer. Additionally, the scent of blood meal sprinkled on the ground around plants often serves as an effective deterrent.
A motion-triggered sprinkler often discourages deer, because the animals don't appreciate the strong blast of water directed their way. Keep in mind that the motion sensors detect any motion, including human visitors, children and pets, as well. Other tactics include shiny Mylar balloons, motion-detecting strobe lights, flashing lights set on timers or a baited device that administers a mild electric shock to the deer's mouth. If you have an energetic dog, try tethering the dog near the ivy when the deer are most active in early morning and evening. These tactics -- even barking dogs -- are often temporary because deer are adaptable and fearless.
Many types of ivy, including English ivy (Hedera helix) are included on noxious or invasive plant lists in several states. The hardy vines grow over native trees and shrubs, eventually causing death by shutting out all available sunlight. Additionally, the ivy becomes so heavy that the underlying plant is weakened and prone to damage and disease. Often, growing ivy in a container or hanging basket is the safest way to enjoy this attractive but rambunctious vine. Otherwise, monitor the plant closely to be sure it doesn't escape its boundaries.