Fruit trees such as a plum tree are an ideal addition to any garden or landscape. Unfortunately, they are ideal for several pests and critters, such as opossums, skunks and especially raccoons. Raccoons can be damaging to your plum tree, so it is important to keep them away. Remember basic things to keep raccoons away, such as tightly cover trash cans to reduce foraging and to clean up food from trees that has fallen to the ground. There are some key things to keep in mind when deterring raccoons, such as ammonia soaking to a high fence.
Soak an old towel in ammonia. Ball up the towel and place it at the base of the plum tree. You can also wrap it around the base of the tree. Raccoons detest the smell of ammonia, so this is a good start to keeping them away from your plum tree.
Us a pest repellent spray such as Capsaicin to discourage the raccoons.
Use fruit tree netting to protect individual plum trees or rows. These are very effective but take some time and preparation to secure. Make sure you fasten the netting to the trunk or the ground, so the raccoons cannot crawl underneath.
Use a fence if all else fails, right around the base of the trunk that's at least four feet high. Raccoons give up easily, so if there is an obstruction in their way to the plum tree they will most likely give up.