Verbena is a popular flowering plant, often chosen by gardeners for its vibrant, long-lasting blooms and ease of care. These ornamental plants include both annual and perennial varieties, offering a range of colors from lavender and purple to white and pink. The question of whether these attractive flowers can withstand hungry wildlife is a common concern. Generally, verbena is classified as a deer-resistant plant, meaning it is not a preferred food source for browsing deer.
Verbena’s Palatability to Deer
While verbena is generally avoided by deer, no plant is entirely deer-proof, and this species is rated by some university systems as “seldom severely damaged.” Deer are highly opportunistic feeders whose diet is primarily driven by immediate necessity and availability. They typically bypass verbena in favor of softer, more palatable foliage found in the garden or surrounding landscape.
Consumption of verbena usually occurs under specific environmental pressures where preferred food sources are scarce. This includes periods of extreme drought, heavy snow cover, or high deer population density. Young deer are prone to sampling plants before establishing adult preferences. A deer will consume verbena if the energetic cost of finding an alternative meal outweighs the plant’s natural deterrents.
General Characteristics of Deer-Resistant Plants
The primary reason deer avoid certain plants, like verbena, stems from specific biological and chemical defense mechanisms. Many plants produce volatile oils that release a strong, aromatic scent when the foliage is crushed. These pungent odors, often pleasing to humans, are highly unappealing to a deer’s sensitive sense of smell, acting as an immediate deterrent.
Another powerful defense mechanism is the physical texture of the leaves and stems. Deer prefer soft, smooth foliage and are put off by plants that have a coarse, fuzzy, or hairy surface. This texture creates an unpleasant mouthfeel, causing them to move on. Furthermore, some resistant plants contain mildly toxic or intensely bitter chemical compounds. These compounds signal that the plant may cause digestive upset or is nutritionally poor, leading to conditioned avoidance.
Minimizing Deer Browse in Gardens
For gardeners in areas with high deer activity, relying solely on plant resistance is often not enough, making a multi-pronged approach necessary. Physical barriers offer the most reliable protection, with fencing being the most effective measure to exclude deer entirely from a garden space. A fence must be at least seven to eight feet tall to prevent leaping and secured to the ground to prevent crawling underneath.
Commercial deer repellents can be used as a secondary line of defense, and these products generally fall into two categories: area and contact. Area repellents use strong odors, often derived from putrescent egg solids or predator urine, to scare deer away from a zone before they feed. Contact repellents are applied directly to the plant foliage and use bitter or spicy compounds, like capsaicin, to create an unpalatable taste.
Since deer can become accustomed to a single deterrent, it is important to rotate between different types of repellents every few weeks to maintain their effectiveness. Repellents must also be reapplied regularly, especially after rain or when new plant growth emerges, as fresh growth will not be protected by the initial application.