Cleome, often called the Spider Flower, is a popular annual plant prized for its unique, airy blooms. It is frequently included in gardens where deer are a concern because it is generally categorized as a deer-resistant option. However, being deer-resistant is not the same as being entirely deer-proof.
Why Cleome is Generally Avoided by Deer
Cleome’s resistance stems from a combination of physical and chemical deterrents that make it unappealing for deer. The stems are covered in sharp, sticky spines or fine hairs, giving the foliage a bristly, unpleasant texture. Deer prefer smooth, tender leaves and typically avoid plants that require a difficult chewing process.
The Spider Flower also possesses a strong, pungent odor that serves as an immediate warning to grazing animals. This musky fragrance is highly undesirable to deer, which rely heavily on their sense of smell to locate food. Furthermore, the foliage contains bitter-tasting compounds, which discourage continued browsing even if the initial texture is overcome. This combination of physical deterrents, strong scent, and bitter flavor causes deer to pass over cleome for more palatable food sources.
Factors That Reduce Resistance
No plant is completely immune to deer browsing, and several environmental factors can override a deer’s natural aversion to cleome. The primary factor is extreme food scarcity, such as during severe winter weather or prolonged drought. When deer are under nutritional stress, they may be compelled to consume plants they would normally ignore.
Local population density also plays a role; high numbers of deer increase competition for food, making less desirable plants a potential target. Additionally, young, newly sprouted cleome or tender new growth may lack the full concentration of bitter compounds or the hardened spines of mature plants. This softer material is occasionally sampled by deer, especially young animals learning what to eat.
Protective Measures for High-Risk Areas
For gardeners facing heavy deer pressure, a layered approach is necessary to safeguard even resistant plants. Physical barriers provide the most reliable defense. This includes installing temporary netting or a low, wire-mesh fence around new plantings until the cleome is established and its spines have hardened. The fence does not need to be tall, as the physical challenge combined with the plant’s natural deterrents is often sufficient.
Applying commercial chemical repellents can also be effective, especially those containing putrescent egg solids or capsaicin, which deter deer through taste and scent. These products require reapplication following heavy rain or every few weeks to maintain efficacy, as new growth is always unprotected. Strategic placement can also help, such as planting cleome close to a home or a walkway where frequent human activity makes deer less comfortable browsing.