Deer absolutely eat watermelon, considering the sweet, hydrating fruit a highly palatable food source. This presents a challenge for home gardeners and commercial growers, as a single deer can cause significant damage to a patch quickly. The strong attraction often draws local deer populations, making crop protection a necessity.
The Deer’s Diet: Watermelon’s Appeal
Watermelon is intensely attractive to deer due to its high sugar content, providing a fast and concentrated source of energy. This sweetness makes it a desirable target, especially when other browse materials are less abundant. The fruit’s high water content also offers a significant source of hydration, appealing during dry seasons.
Deer consume the entire fruit, not just the soft flesh. They often use their hooves or teeth to puncture the tough outer rind to access the interior. Once broken open, the entire melon, including the rind, is readily consumed because it is easier to digest than woody browse. Deer also eat the leaves, stems, and vines, destroying the crop before the fruit ripens.
Health and Safety Considerations
Despite their enthusiasm, excessive consumption of high-sugar foods like watermelon poses a serious health risk to deer. Deer are ruminants, possessing a four-chambered stomach, designed to break down high-fiber, low-carbohydrate browse. A rapid shift to a diet heavy in fermentable carbohydrates, such as fruit sugars, disrupts the microbial balance within the first stomach, the rumen.
This disruption leads to lactic acidosis, or grain overload. Carbohydrate-fermenting bacteria rapidly produce large amounts of lactic acid, causing the rumen’s pH to drop drastically. This low pH kills the fiber-digesting microbes essential for normal digestion. An affected deer experiences severe dehydration and incoordination, and may die within 24 to 72 hours due to systemic failure.
Any practice that concentrates deer in a small area, such as providing a food source, increases the risk of disease transmission. Deadly conditions like Chronic Wasting Disease (CWD) and Bovine Tuberculosis (TB) spread rapidly through direct contact or through contaminated saliva and feces left at communal feeding sites.
Protecting Your Produce
Protecting a watermelon crop requires establishing effective physical or sensory barriers, as passive methods rarely succeed against determined deer. Physical exclusion through fencing is the most reliable method, but it must meet specific height requirements. A single, vertical fence needs to be at least seven to eight feet tall to prevent deer from jumping over it.
An alternative is using a double-fence design with two shorter barriers spaced about five feet apart. This confuses the deer’s depth perception and discourages a jump. For smaller patches, a simple electric fence with two or three wires placed at different heights can be effective by delivering a harmless shock.
For chemical deterrence, commercial repellents based on putrescent egg solids create an unpleasant odor and taste. To prevent deer from becoming accustomed to a single product, alternate between different types of repellents, such as those with strong scents like mint or garlic. Apply these every few weeks and especially after heavy rain.