Dahlias, known for their diverse colors and showy blooms, are a popular addition to gardens. These flowers grow from tuberous roots and provide color from midsummer until the first frost. Gardeners often worry about protecting these plants from local wildlife, particularly browsing animals.
Dahlia Vulnerability to Deer
Dahlias are generally considered less palatable to deer compared to many other common garden plants. The foliage possesses a slightly pungent, peppery scent and taste, which deer typically find undesirable and tend to bypass for tastier options. This natural defense suggests dahlias are not a preferred food source.
However, no plant is entirely deer-proof, especially when natural food sources become scarce. A hungry deer, particularly during periods of drought or high population density, will readily consume almost anything available, including dahlia foliage and flower buds. Damage from deer is characterized by a ragged, torn appearance on the stems or leaves. Deer lack upper incisor teeth, meaning they must yank and rip the plant material rather than making a clean bite. Deer browsing typically occurs at a height range of two to six feet, targeting the upper parts of the plant.
Dahlia Vulnerability to Rabbits
Rabbits often pose a more consistent and destructive threat to dahlias than deer, particularly earlier in the growing season. These smaller herbivores prefer to feed close to the ground, targeting tender new shoots and emerging foliage. A young dahlia is especially susceptible to being completely destroyed by a rabbit before it develops tougher mature leaves.
The type of damage inflicted by rabbits is distinctly different from that of deer. Rabbits possess sharp upper and lower incisors, allowing them to make clean, angled cuts across stems and leaves, much like a pair of scissors. This damage is concentrated from the soil line up to about two feet. While a mature dahlia plant may be large enough to withstand some rabbit browsing, the loss of early growth can severely stunt the plant’s development and bloom potential.
Strategies for Protecting Dahlias
Protecting dahlias requires employing a layered strategy that addresses the specific feeding habits of both deer and rabbits. Physical barriers offer the most reliable defense, particularly for young plants. Low-height fencing, such as chicken wire or hardware cloth, installed around emerging dahlias can effectively deter rabbits. For deer, a fence must be significantly taller, typically eight feet or more, as they are capable of jumping considerable heights.
Chemical and olfactory deterrents can be applied as a secondary line of defense to make the plants unappealing. Commercial repellents, which often contain active ingredients like dried blood, putrescent egg solids, or capsaicin, work by taste or smell to discourage browsing. These products must be reapplied regularly, especially after rain or when new growth emerges, to maintain their effectiveness.
Strategically placing dahlias near the home or in areas with consistent human activity can also reduce the likelihood of nocturnal browsing. Companion planting involves placing dahlias next to strongly scented herbs like sage or rosemary. The aroma of these plants can help mask the dahlia’s scent, making them harder for deer to locate.