Answer: Deer are a real problem for many gardeners. Lists of deer-resistant plants exist but I must warn you...if they are really hungry they'll open your front door, jump over you stretched out in the recliner watching TV, open the refrigerator and grab the lettuce in the crisper drawer! In other words, hunger expands their palate and increases their bravery.
Lots of deer deterents are available for gardeners under a variety of names. Results vary. Sprays of egg solids, hot pepper oil and other such ingredients may help some, especially when the deer "pressure" is not too high. Human hair (from the local barber shop) and bags made of hosiery and highly scented soaps work on occasion. Animal and human urine, as well as lion dung, have been said to be effective in keeping them at bay. Other reported deterrents include high pitch sounds and fishing line stretched across their usual route through your area. Small gardens can be protected by electric fences if they are high enough! But deer are not stupid, and eventually they get use to many of these tricks. Some gardeners have had luck alternating use of a variety of these or similar deterrents to keep them from getting too comfortable.
Another great deterrent is one that you already mentioned--a dog! Dogs are threatening enough to deer that they will stay clear of any area that has their smell. A dog doesn't need to be confined to the garden area to be effective. Just walking the dog through the area and allowing it to mark the territory is usually sufficient.
As with all animals, dogs are a responsibility and should not be left outside in an unfenced area especially at night. If they get the scent of deer (or rabbits) they will likely take chase. While it seems it may cure your deer problem, it can cause many other problems.
Sometime the best remedy for deer is a change in attitude: enjoying these elusive creatures, realizing that they are an essential part of nature, and accepting some loss of produce in exchange for sharing the land with them. Good luck with the deer!
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