Bean plants, including common varieties like green beans, pole beans, and bush beans, are popular additions to many gardens. Their tender leaves and developing pods are a highly attractive food source for a wide array of wildlife and garden pests. Identifying the specific culprit responsible for the damage and understanding their feeding patterns is the first step in implementing effective control measures.
Identifying Damage Patterns and Likely Culprits
Deer damage is often characterized by ragged, torn leaves and stems, usually occurring above two feet from the ground. Since deer lack upper incisors, they tear foliage rather than cleanly biting it, leaving a distinctive messy appearance.
Rabbits possess sharp incisors that leave clean, angled cuts on stems and leaves. Their feeding typically occurs on young seedlings or lower foliage, rarely extending higher than six inches from the soil surface.
Groundhogs, also known as woodchucks, can consume entire plants or large sections of a patch remarkably quickly. If a significant portion of the crop disappears overnight, look for evidence of large, inconspicuous burrow entrances nearby.
Slugs and snails create irregular holes in leaves and pods. The most telling evidence of their activity is the presence of silvery, dried slime trails left across the foliage or on the surrounding soil surface.
Voles, which are notorious burrowers, often create small, visible tunnels or runways near the base of the plant, sometimes causing the entire stalk to collapse. This damage is typically concentrated at or just below the soil surface.
Physical Barriers for Large Animal Exclusion
A physical fence must be at least eight feet high to reliably deter a motivated deer from entering a garden space. Materials like woven wire mesh or specialized poly-fencing are effective, provided the barrier is taut and fully secured to the ground.
When a full eight-foot fence is impractical, alternative designs can exploit the deer’s poor depth perception. Installing two parallel, shorter fences, spaced about four feet apart, can confuse the animal and discourage jumping. Another strategy involves slanting the fence outward at a 45-degree angle, making the perceived jump distance too great.
Fencing designed to exclude smaller, low-crawling animals like rabbits and groundhogs focuses on ground-level security. The fence material only needs to be about two feet high, but it must be made of a sturdy, small-gauge wire mesh. The common mistake is failing to secure the bottom edge against digging.
To prevent burrowing pests from accessing the beans, the bottom of the wire mesh must be buried six to ten inches deep into the soil. For groundhogs, an L-footer design is highly effective, where the buried portion is bent horizontally and extended outward for several inches. This design acts as a deterrent barrier when the animal attempts to dig under the vertical fence line.
For protecting small, vulnerable bean seedlings, temporary physical barriers offer immediate relief. Cloches or row covers draped over hoops can shield young plants from early browsing pressure. Chicken wire cages, secured firmly to the ground, also provide an effective, rigid barrier.
Targeted Control Methods for Small Pests and Rodents
Controlling slugs and snails often involves targeted baits or habitat modification, as physical fencing is ineffective. Organic baits containing iron phosphate are safe for gardens and disrupt the mollusk’s digestive system after ingestion. Alternatively, shallow traps filled with beer can attract and drown the pests, offering a non-chemical solution.
Reducing the dark, damp hiding spots where these pests congregate is another effective cultural control method. Gardeners should remove excess mulch, weeds, and debris from the base of the bean plants. Watering the garden in the morning rather than the evening allows the soil surface to dry before nightfall, making the environment less hospitable to slugs.
Managing voles and mice requires attention to habitat and population control. Removing tall grass and brush around the garden perimeter eliminates protective cover, making the area less appealing to these rodents. Small, protective wire mesh cylinders can also be placed around the base of individual stems to prevent gnawing damage.
Trapping remains a reliable method for reducing localized rodent populations, utilizing multi-catch live traps or traditional snap traps placed near known runways. Repellents, which work by taste or scent, can also offer temporary protection. Taste-based products, often containing capsaicin or bitter agents, deter the animal upon tasting the foliage.
Scent-based repellents, such as those derived from garlic or predator urine, must be reapplied frequently, especially after rain, to maintain their efficacy. Bean plants are also susceptible to insect pests like aphids and Japanese beetles, which are controlled using different methods. Simple solutions include handpicking beetles or applying insecticidal soap to manage soft-bodied pests like aphids.