An adult deer eats between 4 and 8 pounds of food per day, and isn't picky.
Few animal pests do more landscape damage than the common deer.
A typical adult deer eats between 4 and 8 pounds of food a day. In a deer’s eye, that patch of hosta and grouping of foundation azaleas you just planted are a dinner buffet. Because deer are vegetarians, landscape plants serve as increasingly important food sources, especially in winter when native vegetation is in short supply.
How can deer and gardeners co-exist? The only sure-fire way to prevent damage is to erect a fence between the deer and your plantings. That’s the approach used by most public gardens located in deer-populated areas.
Deer are prolific jumpers, so fence heights of at least 8 feet are recommended. Alternatives are two parallel fences erected at least 5 feet tall and 5 feet apart or a single fence at least 6 feet tall that’s angled outward at 30 degrees.
If it’s not practical or possible to fence the entire yard, spot-fencing can be erected around particularly threatened plantings. Deer tend to pick out young and tender plants, so it’s possible the fencing no longer will be needed once the bark toughens.
Another approach that can limit damage is by picking plants that deer like the least. The theory is that deer will fill up first on plants they like best, and so if you stick with choices they don’t favor, they may find a neighboring landscape tastier. Or, they may be more content with what’s growing wild along their favored pathways.
An 8-foot fence is one of the surest ways to deter deer from eating a landscape.
Plants less palatable to deer include trees such as birch, flowering pear, goldenrain, serviceberry and stewartia; evergreens such as boxwood, falsecypress, nandina, mahonia and most spruce; shrubs such as bayberry, caryopteris, abelia, spirea, Virginia sweetspire and St. Johnswort; and perennial flowers such as amsonia, bleeding heart, catmint, coreopsis, ferns, goldenrod, iris, salvia and yarrow. However, deer get less picky as they get hungrier, so keep in mind that even so no plants are truly deer-resistant.
Deer and animal repellents
Numerous commercial spray and granular repellents are available in garden centers. Most contain smells that deer find repulsive (rotten eggs and garlic are two common ones) or tastes that ruin the flavor of your azaleas.
Home gardeners also often whip up their own concoctions, using ingredients such as bloodmeal, ammonia, garlic, hot pepper sauce and eggs. One recipe suggested by the Humane Society of the United States involves mixing 4 eggs, 2 ounces of hot pepper sauce and 2 ounces of chopped garlic into 1 quart of water, then straining it and spraying it on targeted plants. Other gardeners employ hanging bags of bloodmeal, bars of deodorant soap and bags of human or dog hair.
The main down side of repellents is that the scent and taste wears off, especially in frequent rains. Frequent reapplications are necessary to keep the repellant fresh.
Deer also sometimes adapt to repellents, so alternating recipes may afford better protection repeating the same concoction.
Scare tactics work, too
Finally, scare tactics sometimes help. Barking dogs and aluminum pie pans hung on string are age-old weapons. A newer and higher-tech option is rigging up a motion sensor to a garden hose, radio, light or noise-making device. All are designed to startle deer and turn their attention from dinner to survival if they enter the sensor-protected area. As with repellents, it’s best to rotate scare tactics to prevent deer from realizing they’re just a ruse and not a real threat.