Comfrey (Symphytum species) is a popular perennial herb valued for its rapid growth and deep taproots. This vigorous plant often serves as a beneficial addition to garden ecosystems, accumulating nutrients. Gardeners frequently inquire about its susceptibility to grazing animals, particularly deer.
The Definitive Answer: Comfrey’s Status
Comfrey is widely considered a deer-resistant plant and is rarely browsed. While no plant is completely “deer-proof,” especially when resources are scarce, comfrey consistently ranks high on lists of plants that deer naturally avoid. The distinction between “resistant” and “proof” is important, as a starving deer may eat almost anything, but under normal circumstances, comfrey is a low-priority food source. Gardeners in areas with high deer populations can generally rely on comfrey to remain untouched.
The plant’s inherent characteristics make it unpalatable and mildly irritating to grazing wildlife. Deer are selective browsers, and they tend to avoid foliage that presents a physical or chemical deterrent. This natural aversion means that the plant offers a reliable option for landscapes where deer presence is a concern.
Attributes That Deter Deer
Deer avoid comfrey due to its physical texture and chemical composition. Comfrey leaves and stems are covered in fine, stiff hairs, giving the foliage a rough feel. This physical texture, known as hirsute, is generally unpleasant for a deer’s sensitive mouth and digestive tract. Deer prefer smooth, tender vegetation, making the scratchy surface of comfrey a mechanical deterrent.
The second deterrent is the presence of pyrrolizidine alkaloids (PAs) within the plant tissue. These compounds give comfrey a bitter taste, acting as a natural defense against herbivory. The bitterness signals to deer that the plant is not a desirable food source.
Integrating Comfrey into a Deer-Prone Landscape
Gardeners can strategically use comfrey’s deer-resistant properties to protect other, more vulnerable plants. Planting comfrey as a “buffer plant” or border around gardens creates a natural perimeter deer are less inclined to cross. The dense, wide-spreading foliage acts as a physical barrier to less resistant crops.
Choosing a resistant variety like Russian comfrey (Symphytum x uplandicum) can enhance this protection. Cultivars such as ‘Bocking 14’ are sterile hybrids, meaning they do not set viable seed, which prevents them from spreading aggressively. This characteristic makes them a manageable and long-lasting defensive plant. Placing comfrey strategically at the edges of a property or along fence lines can help redirect deer away from favorite browsing targets.