Bee Balm (Monarda) is a perennial herb native to North America and a member of the mint family (Lamiaceae). It is recognizable by its unique whorled flowers and square stems. The foliage contains high concentrations of aromatic oils, such as thymol and carvacrol, which create a distinct, pungent scent. This strong fragrance acts as a natural deterrent, making the plant resistant to browsing mammals. However, this defense is not foolproof, and various animals and insects will still consume the plant, especially under certain environmental conditions.
Mammalian Herbivores
Deer and rabbits are the most common large mammals that occasionally graze on Monarda despite its strong flavor. Although Bee Balm is categorized as deer-resistant, it is not immune to being eaten, especially when food sources are scarce. Environmental stress, such as drought or deep snow cover, can push these animals to consume less palatable plants.
Rabbits and deer typically target the most tender parts of the plant, often nipping off young shoots in early spring. Damage is identified by a clean-cut appearance on the stems or leaves, as browsing mammals lack the incisors to tear foliage. Heavy browsing pressure is indicated if a large portion of the plant is eaten down to a nub. The plant is resilient and often recovers from moderate browsing by generating new growth.
Insect Pests That Consume Foliage
Smaller invertebrate pests actively chew and consume the plant’s tissues, leaving specific damage signatures. Slugs and snails are soft-bodied mollusks that feed on young shoots and stems, especially in damp, cool conditions. They create large, irregular holes in the leaves. Their presence is often confirmed by the tell-tale silvery slime trails left on the foliage and surrounding soil.
The Stalk Borer, the larva of the Papaipema nebris moth, is a destructive threat that tunnels directly into the plant’s stem. This internal consumption of the core tissue causes the upper part of the stem to suddenly wilt and die. The Mint Flea Beetle is another chewing pest; this tiny, dark beetle feeds on leaves, creating small, round perforations known as “shotholes.” This damage is concentrated on new foliage, giving the leaves a lacy or riddled appearance.
Caterpillars, such as the larva of the native Raspberry Pyrausta Moth (Pyrausta signatalis), chew on the plant, often targeting flower buds and developing blooms. Gardeners may also encounter cutworms, which are moth larvae that live near the soil line. Cutworms sever young stems at the base, causing the entire plant to collapse. Identifying the precise damage pattern helps distinguish between large mammal browsing and specific insect consumption.
Strategies for Protecting Bee Balm
Protecting Bee Balm from browsing mammals involves physical barriers and scent-based deterrence. Installing a sturdy wire fence is the most reliable method for keeping out deer and rabbits, especially near wooded areas. If a physical barrier is not feasible, commercially available repellent sprays can be effective. These products utilize strong odors or tastes to discourage feeding.
Control of chewing insect pests and mollusks requires specific, targeted methods. Stalk borers are best managed through sanitation. Removing and destroying affected stems immediately prevents the larva from maturing and reduces future egg-laying. Since the moth lays eggs in tall weeds and grasses, keeping the area around the Bee Balm free of debris is important for prevention.
Slugs and snails can be managed by handpicking them at night or by setting beer traps, which attract and drown the pests. Utilizing iron phosphate pellets is an organic control option that is safer for pets and wildlife than traditional molluscicides. For chewing beetles and caterpillars, handpicking is often sufficient. This should be combined with cultural practices like ensuring good air circulation and thinning crowded clumps, which helps the plants stay vigorous and outgrow minor damage.