One of the most common questions that gardening stores receive throughout the year from homeowners and gardening enthusiasts is from those who are seeking a deer repellent that works. And while many gardening stores carry a wide variety of not only deer repellents, but plants and trees that deter and repel deer, a store employee need only to send a homeowner with a deer problem back to his or her kitchen to mix up a simple solution that will keep even the hungriest deer away from prized flowers and vegetables.
The deer repellent that works best in any climate and at any time of the year is the one that has one simple ingredient: egg. One raw egg can be mixed at home with almost any amount of water, from one cup to a gallon, depending on how much is needed, and what strength is found to be most effective after some trial runs of using it. After mixing the two ingredients, the mixture will work even better if left in the sun for a few hours in order to cause the eggs to putrefy. The smellier the mixture becomes in the heat of the sun, the more effective it will be at deterring the voracious deer from the garden plants. While the mixture will emit a very unpleasant odor, once sprayed and dried on the leaves of the plants, the odor will not be noticeable, except to the keen sense of smell that deer, and other garden pests like rabbits, have.
Recent studies have demonstrated that the same egg and water mixture, used with putrefied egg solid (cooked) instead of raw egg, works even better and repelling hungry deer. An egg can be quickly cracked and then cooked in a microwave safe mug or measuring cup. Egg solid is more likely to clog a sprayer applicator, so it should be gently dribbled on any plants that attract deer. A few tablespoons of vegetable oil or canola oil can be added to the mixture, and will make the repellent cling to plant leaves more easily. Egg solid is also preferable to homeowners who wish to avoid contact with raw eggs, or who have children or pets who may come into contact with the spray once is it on the plants, because raw eggs can carry a salmonella risk. Dogs, especially, are not known to be picky eaters, and may be attracted to all sorts of food that deer and humans find nauseating.
Motion detecting sprinklers, walls, and fences are commonly used to keep deer away from plants. Prickly and thorny shrubs are somewhat effective when there are plenty of softer food choices around, but in a food shortage, a hungry deer will eat any kind of plant. Repellents made from coyote or wolf urine, sold in hunting stores, are sometimes touted as effective for repelling deer, but they have an offensive odor, can be expensive, and most studies find them even less effective than the more simple egg and water mixture. So when asked, a gardening expert will always send you to your kitchen to find a deer repellent that works.