Deer damage is one of the biggest concerns facing property owners in the local area today. To many homeowners, the threat of insect or disease problems pales in comparison to the agony of knowing that at any moment a passing deer may devour part of the landscape.
The solution is not easy to track down. Individual deer seem to vary in their plant tastes and the degree to which they are thwarted by different repellents. As the manager of a local garden center and a homeowner, I have gathered insight into dealing with the deer problem.
At the heart of the matter is the fact that deer are eating machines. Although we can't match their appetites, most of us possess a superior intellect.Common sense tells us right away that (1) deer can't eat what they can't get at, and (2) they are less likely to eat what smells or tastes unattractive. Probably, the best way to deter deer is with a physical barrier. One option is always to fence the whole yard. For many, that would be impractical due to cost or unsightliness. Many people achieve great results by fencing vulnerable groups of plants within a yard. Feedback suggests that the best materials are tough poly or metal fencing.
Tenax deer fence is easy to work with, tough, and visibly tolerable. It should be supported by metal T-stakes or 2x2" wooden stakes and attached with twist ties or plastic zip-ties. A good height is 7-8' and the fencing should be placed within a few feet of the plants it's protecting. Deer are unlikely to jump over a fence when they can't perceive a clear landing on the other side. If the fence is being used as a property perimeter, it should be higher. Plastic trunk protectors can be placed on young shade and flowering trees to prevent ‘buck rub’ and rodent damage.
For people who don't like fencing, there are dozens of products that can be applied to the plant, that smell or taste bad, or both. The best deer deterrent sprays are extremely bitter and adhere to surfaces for as long as a month. The more popular are Bobbex, Tree Guard and Liquid Fence. My experience is that all of these are extremely effective. As anything will wash off with time and weather, failure is often due to inadequare re-application. In my opinion, Tree Guard and Bobbex work best due to their extreme adherence. In fact, Tree Guard is so sticky that if the spray mechanism isn't washed out thoroughly with hot water it won't spray the next time. The key to all of them is re-application at the right time - more often if there has been a lot of precipitation.
Some people get excellent results from methods that typically have a lower success rate, such as tallow based soaps, human hair clippings, or Milorganite. Milorganite is an organic fertilizer with deterrent properties. Soap and hair would be used at 4 or 5 portions per 3-4' shrub. All of these work by scent and are very successful when feeding pressure is low. Coyote Urine is a method to widen the eyes, but the fact is, feedback tells me it works well. It is applied to small absorbent sponges and placed around the plants. Two people have told me it also attracted Coyotes which may or may not be an added benefit depending on your point of view.
Choosing plants that deer are less likely to prefer is always a prudent strategy, but remember that deer are fickle and vary in their tastes. Plants very seldom bothered in the local area are Boxwood, Japanese Andromeda, Colorado and Norway Spruce varieties, Barberry, Daffodils, and Muscari. Plants that deer adore eating include Arborvitae, Yews, Rhododendrons, Azaleas, and Tulips.
At my Genoa home, I’m lucky to have no problem with deer even though they are all around. In rural areas deer just haven't had to learn that yards are an excellent source of food. From listening to people over the years and seeing what products people come back to purchase again, or return, my final advice would be to use a mixture of methods. Buy deer resistant plants. Use sturdy fencing and apply one or more of the better repellents. Local garden centers are the best sources of collective deer deterrent advice and most will have a good list of deer resistant plants.