The perennial garden plant, rhubarb, is known for its tart, edible stalks used in pies and sauces. Deer are a primary concern for gardeners across many suburban and rural landscapes. This frequently leads to the question of whether deer will target the plant’s large, distinct leaves.
Deer Preference: Do They Eat Rhubarb Leaves?
Deer generally avoid eating rhubarb leaves, which is why the plant is often listed as “deer-resistant” in gardening guides. The leaves are not a preferred food source for white-tailed deer, even when other food becomes scarce. While a very hungry deer might take a sample bite, they rarely consume the leaves in significant volume. This low preference allows rhubarb plants to thrive even in areas with high deer populations.
The unpalatability of the leaves helps preserve the plant’s structural integrity, unlike other garden vegetables that deer strip completely. Deer are primarily browsers, preferring leaves, shoots, and soft stems, but they are selective in their foraging. Their instinct steers them away from plants that offer little nutritional reward or cause discomfort.
The Chemical Barrier: Oxalic Acid
The primary reason deer avoid rhubarb leaves is the presence of high concentrations of oxalic acid, also known as oxalate. This naturally occurring compound acts as a chemical deterrent against herbivores. The leaves contain significantly higher levels of oxalic acid than the edible stalks, which is why only the stalks are consumed by humans.
When ingested, oxalic acid binds with calcium in the digestive tract, causing internal irritation and a bitter taste. In large quantities, the formation of calcium oxalate crystals can lead to serious issues, including kidney damage. Deer instinctively detect and avoid this unpleasant compound.
General Deer Browsing and Damage
If deer are present, they will almost certainly be targeting plants other than rhubarb. Deer favor tender, protein-rich plants, especially new growth and succulent garden favorites. Common targets include hostas, tulips, roses, daylilies, and young fruit tree shoots. Deer often tear the vegetation, leaving a ragged edge because they lack upper incisors.
Any damage observed on rhubarb is likely incidental, such as trampling from a deer moving through the garden to reach a more palatable crop. Deer may occasionally nibble the less toxic stalks, especially younger, tender portions that have a lower concentration of oxalic acid. Gardeners should focus protection efforts on plants known to be deer “candy” rather than the naturally protected rhubarb.
Methods to Deter Deer from Gardens
Protecting the rest of the garden requires a multi-faceted approach, as deer quickly become accustomed to any single deterrent. Physical barriers are the most reliable long-term solution. A fence should be at least eight feet high to prevent deer from jumping over it, or two shorter fences placed several feet apart can confuse their depth perception.
Commercial repellents offer a temporary fix, using unpleasant scents (such as rotten eggs) or bad tastes to discourage browsing. It is important to rotate these products regularly to prevent deer from habituating to the odor or flavor. Planting highly aromatic companion plants, such as sage, rosemary, or lavender, around preferred plants can help mask the scent of desirable food sources. Motion-activated sprinklers that spray a sudden burst of water can also startle deer.