You’ve prepared the soil and planted your garden, but now you may be faced with uninvited guests. Since deer are creatures of habit and a small number can do a great deal of damage, the quicker you act to deter them, the better. Thankfully, there are a lot of things you can try.
There are many smells that may deter your local grazers including commercial deer repellents, blood meal, mothballs, fabric softener, decaying fish heads, and garlic (Better Homes and Gardens). Since different breeds and populations of deer have different tastes, you may need to do some experimenting to find what works best, and these methods may need to be reapplied after rain.
Some gardeners hang bars of strong-smelling soaps such as Irish Spring around their plants. Another option is to use a vegetable peeler and drop the soap shavings around low-growing plants. Benefits of the soap method include less frequent re-application (it lasts for about a month), it is not harmful to plants, and it can even decrease unwanted pests such as aphids which the soap dehydrates (Good Housekeeping). Irish Spring is not your only soap option, though you should avoid bars with coconut oil, which may actually attract deer (Good Housekeeping).
Another option is making your own concoction out of ingredients such as milk, yogurt, eggs, cayenne pepper, garlic, or other strong-smelling substances. There are myriad recipes on the internet if you are interested in this method, the downside of which is obviously that you will be smelling the deterrent too.
Luckily, there are some plants that deer, like to avoid that, may be more pleasant for the human nose. Lavender, marigolds, and fragrant herbs such as mint, oregano, or catnip can be good deterrents, though you may need to plant quite a few marigolds, and mint plants in the ground can become invasive.
Hanging pie tins or aluminum cans from stakes, fences, or tree branches can be a great way to deter deer, as they reflect light and make noise, especially if there is a breeze. A similar idea is to install motion-activated sprinklers which tend to startle unsuspecting grazers.
When all else fails, there is also the option of a physical barrier. To keep deer out, you will need a fence that is fully enclosed and at least eight feet high. A shorter fence (six feet or so) may also work if it leans outward, making it more difficult for deer to jump. If you want to avoid a heavy-duty structure, you may opt for a durable fishing line. This method allows for a shorter fence (around three feet) and should include a second fence a few feet out from the first with some ties or other visible material on the lines for the deer to see for best results (Chicago Tribune).
Whatever method you try, you will achieve the best results if you mix up your approach (unless your solution is the sturdy fence), as deer are likely to realize over time that what initially deterred them is not as undesirable as it at first seemed.