Deer Defense by Carole Ottesen

Dealing with these garden marauders requires a varied strategy and vigilance.

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The population of white-tailed deer (Odocoileus virginianus) has grown from under half a million to an estimated 20 million nationwide over the last few decades. White-tailed deer are now ubiquitous in all but a few western states where mule deer inhabit their niche. The loss of wildlife habitat combined with their burgeoning numbers have caused these usually reclusive mammals to invade agricultural as well as suburban and urban areas. There, they ravage crops and gardens—including, very likely, your own.

If you have ever awakened to find 40 hostas chewed to bare stems in a single night, if your arborvitaes sport hourglass figures, if your azaleas or roses don’t bloom, and your strawberry bed has disappeared, read on. You’ll find not only sympathy, but also strategies for protecting your garden.

For most gardeners, the kind of damage deer do to plants is not easily ignored. Because of the way deer eat—by shredding the tissues—deer damage doesn’t usually kill outright, it maims. Maimed plants are more susceptible to disease, become stunted with continual deer browse, and are unattractive.
When faced with a deer problem, gardeners usually turn to repellents as a first line of defense, and for good reason: They’re readily available and easy to use.

Types of Repellents

There are three general types of repellents. The first type, most often in spray form, makes plants taste bad. There are also extremely bitter systemic tablets. Best used when putting new plants into the ground, the tablets need over a month to be absorbed but last up to three years.

There are plenty of commercially available repellents of the bad-tasting type, but one of the most effective is a homemade mixture of 20 percent whole eggs and 80 percent water. If you apply it on a dry day when temperatures are above freezing, it should last about a month. Take the membrane off the yolk to help keep your sprayer from clogging—at least for a while.

The second kind of repellent smells bad. Repellents based on aroma work best in the warmer months. “In winter,” says garden writer and photographer Karen Bussolini, who gardens on a “deer-infested mountainside ” in Connecticut, “the aroma molecules don’t disperse into the air as well.”

Do-it-yourself malodorous methods include spreading bloodmeal, hanging mesh bags of human hair, or dangling strongly scented soaps such as Irish Spring or Zest from or very near—within 30 inches of—susceptible plants. The bloodmeal works for a short while, but may attract local dogs and other carnivores. There are mixed reviews of human hair, but many gardeners swear by the soaps—although there are a few who report that the deer actually eat it. Also, some gardeners have found that when fish emulsion is applied as a foliar feed, it can act as a deer repellent as well.

The third type of repellent combines bad odor with bad taste. Products such as Deer-Off, Deer Solution, and Not Tonight Deer! are examples of these. (See “Sources” on page 32 for a list of some mail-order companies that offer deer-deterring products.)

Effective Use of Repellents

After trying a multitude of products ranging from coyote urine to soap, I have found that repellents will help keep deer from devouring plants if—and only if—they are applied relentlessly and continually. This is one of the biggest problems with using repellents. If you let up on the application, even just for a week because the deer seem to be keeping away, sure enough, there will come a night when the hostas (tulips, daylilies, roses, etc.) will be chewed up and ruined for the rest of the season. I have also found that repellents work better if you vary them regularly.
Another tip for success with repellents is to apply early—before deer have invaded your garden. Don’t wait to take action until after the fact. “With each new planting,” advises Brad Roehler, manager of the display garden and grounds at the Institute of Ecosystem Studies in Millbrook, New York, “regardless of the time of year that you are planting or the susceptibility of the plant to browsing, spray the plant with an odor-based repellent immediately after planting.” If deer have an unpleasant first encounter with your new plant, explains Roehler, they’re more likely to avoid it in the future.

Dog-Gone effective

Besides repellents, there are several other strategies you can try. Dogs are terrific at deterring deer, but not just any dog will do.…

Photo credits: White-tailed deer courtesy of Fish and Wildlife Service. Soap used as deer repellent by Carole Ottesen

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