The perennial plant Aquilegia, commonly known as columbine, is a favorite among gardeners for its delicate, spurred flowers and fine, fern-like foliage. Appearing in a wide range of colors in late spring and early summer, these attractive blooms are popular for borders and woodland gardens. Columbine is generally considered to be deer-resistant, though this resistance is not an absolute guarantee of safety against browsing.
Classification of Deer Resistance
Columbine is not classified as a “deer-proof” plant, a category that realistically does not exist, but rather falls into a favorable resistance rating. Many university extension offices and horticultural organizations rate Aquilegia as “seldom severely damaged” or “moderately resistant.” This rating means that deer will typically bypass columbine in favor of more palatable plants when other food sources are available. As a low-preference food item, columbine is a sensible choice for landscapes situated in areas with moderate deer populations.
Chemical and Physical Deterrents
The plant’s resistance stems from a combination of internal chemistry and physical structure. Columbine contains toxic compounds, specifically certain alkaloids, which impart a bitter taste to the foliage. Deer possess a highly developed sense of taste and smell, allowing them to instinctively avoid plants with these unpleasant characteristics. In addition to this chemical defense, the plant’s delicate, lobed leaves form a texture that is less appealing than the broad, succulent foliage of other garden plants. This combination of bitter taste and unappealing texture serves as a built-in defense mechanism against herbivores.
When Deer Ignore Resistance
Despite its built-in defenses, columbine can still be browsed under specific environmental pressures. The rating of “deer-resistant” is always relative to the availability of other food sources and the local population density of deer. Deer are opportunistic browsers, and in periods of extreme food scarcity, they may eat almost anything to survive. This desperation is most common during harsh winters or severe droughts when preferred forage is scarce or inaccessible. Furthermore, new, tender growth that emerges in the spring may contain lower concentrations of the defensive alkaloids, making it temporarily more vulnerable to browsing.
Minimizing Deer Damage
Gardeners in areas with high deer traffic can take several proactive steps to protect their columbine plants. One effective strategy is to employ physical barriers, such as temporary netting or protective cages, especially over young plants in the early spring when they are most vulnerable. If the garden is small, a taller, permanent fence may be the most reliable defense, as deer are less likely to jump into confined spaces.
The application of taste-based or scent-based deer repellents can also discourage browsing behavior. These products typically need reapplication after heavy rain or new plant growth to maintain their effectiveness. Strategic planting can also offer a layer of protection by placing columbine near the house or deck, where deer are less inclined to venture. Companion planting with highly aromatic, strong-smelling herbs, such as lavender or sage, can help mask the columbine’s presence and further deter deer.