Squirrels are a common presence in many yards and gardens, and they definitively dig up plants. This behavior is a frequent source of frustration for homeowners and gardeners, as the rodents can quickly disturb newly planted areas. Understanding the biological drivers behind this digging is the first step in effectively managing the problem in your landscape.
The Biological Motivation for Digging
The primary reason squirrels dig is a genetically programmed behavior known as scatter hoarding. This strategy involves burying individual food items, like nuts and seeds, in numerous shallow caches across a wide area for later retrieval. The small holes seen in lawns and garden beds are often the result of the squirrel creating a new cache or recovering an old one.
This dispersal of food helps ensure the squirrel’s survival through periods of scarcity, as they remain active all winter. Squirrels possess an excellent spatial memory to locate a significant percentage of their caches, though forgotten caches contribute to the natural dispersal of tree seeds. They will sometimes perform a “fake bury” to deceive competitors, demonstrating the instinctual nature of the digging action.
A secondary motivation is simple exploratory foraging, where squirrels dig to find existing food sources. They are particularly drawn to areas with loose, freshly tilled soil, which suggests an easy place to find or bury a meal. Newly planted bulbs, such as tulips and crocuses, are a high-value food source that squirrels will actively seek out and excavate.
Identifying Targeted Plants and Damage
Squirrels target soft, nutrient-rich items, with flower bulbs being one of the most common victims, particularly during the autumn planting season. Newly planted seeds, seedlings, and recently disturbed soil around transplants are also highly vulnerable to being dug up. Squirrels are opportunistic omnivores and will even chew on ripe fruits and vegetables like tomatoes, leaving behind distinct bite marks.
The telltale sign of squirrel activity is the presence of multiple, small, conical holes scattered across the soil surface. These holes are typically shallow, measuring about one to two inches in diameter and depth. This differs from the tunnels or long ridges created by burrowing pests like voles or moles.
If you find a plant uprooted and left on the soil surface, or a small, round divot where a nut was once buried, a squirrel is the likely culprit. Damage can also include chewed bark on young trees or the consumption of tree buds in the spring. The damage pattern is erratic and scattered, reflecting their individual caching behavior.
Discouraging Digging
Effective discouragement focuses on making the area unattractive to a foraging squirrel through physical exclusion and sensory deterrents. Physical barriers are highly effective, especially for protecting bulbs and newly seeded areas. You can lay down hardware cloth or chicken wire over the soil surface, which allows sprouts to grow through but prevents digging access.
For bulbs, lining the planting hole with wire mesh creates a secure cage that allows shoots to emerge while blocking access to the food source. Adding a layer of mulch or gravel over the soil can also discourage digging, as squirrels dislike the texture underfoot.
Sensory deterrents exploit the squirrel’s sensitive sense of smell and taste. Applying a repellent containing capsaicin is an effective way to discourage consumption and digging. Other unpleasant scents, such as peppermint oil or apple cider vinegar, can be sprayed around vulnerable plants and soil. Alternatively, planting varieties that squirrels dislike, such as daffodils, alliums, or Fritillaria, creates a natural barrier.