For gardeners across the United States, the threat of deer browsing is a constant concern. Selecting plants that are naturally less palatable to these animals is a key strategy for a thriving garden. When evaluating a plant's deer resistance, it is essential to understand the physical and chemical characteristics that make it undesirable from a deer's perspective.
Cornflowers (Centaurea cyanus) are generally considered to be deer-resistant plants. They are not a preferred food source for deer, who will typically bypass them in favor of more tender, succulent, and aromatic plants like hostas, daylilies, or roses. This classification places them in the "rarely damaged" category, which is a valuable trait for gardeners in areas with moderate to high deer pressure. However, it is crucial to remember that "deer-resistant" is not synonymous with "deer-proof."
The deer resistance of cornflowers can be attributed to their specific physical and textural qualities. Deer have sensitive mouths and generally avoid plants that are hairy, prickly, tough, or fuzzy. The stems and leaves of the cornflower plant are covered in fine, gray-white hairs, giving them a woolly or fuzzy texture. This tactile experience is unappealing to deer, who will usually move on to seek out smoother, more palatable foliage. Furthermore, the plant's overall structure is somewhat wiry and not as juicy or nutrient-rich as many other garden perennials and annuals that deer find irresistible.
While texture is a primary deterrent, other factors contribute to a plant's appeal. Deer primarily browse using their sense of smell rather than sight. Cornflowers do not produce a strong, sweet fragrance that often attracts herbivores; their scent is very mild. Regarding color, deer are red-green colorblind and see best in the blue and yellow spectrum. The vibrant blue hues of classic cornflowers are actually quite visible to them. However, since the flower itself lacks a strong enticing scent and the plant's foliage is unappealing, the bright color alone is not enough to make it a target for sustained feeding.
The designation of cornflowers as deer-resistant comes with important caveats. A deer's feeding habits are highly dependent on local factors, including the size of the deer population, the availability of their natural food sources, and the time of year. In periods of extreme drought, harsh winter conditions, or when their population exceeds the carrying capacity of their habitat, deer may expand their palate and sample plants they would normally avoid. In these situations of heightened hunger, even resistant plants like cornflowers may experience some browsing damage, though they are unlikely to be completely consumed.
