The frustration of watching a promising strawberry harvest disappear is common for many gardeners. Chipmunks, with their small size and persistent nature, are often the culprits responsible for this loss. Protecting a strawberry patch requires a multi-faceted approach focusing on exclusion and deterrence.
Understanding the Chipmunk Threat
Chipmunks are attracted to strawberries because the ripe fruit is a high-value, easily accessible food source rich in sugar and moisture. These small rodents possess a keen sense of smell, allowing them to locate the ripest berries. They are diurnal, meaning they are active during the day, which puts them in conflict with gardeners during prime harvesting hours.
The damage they inflict is often disproportionate to their size, as they rarely consume an entire berry. Instead, a chipmunk typically takes a single, small bite out of many different berries, ruining the entire crop for human consumption. This behavior is a form of opportunistic foraging, allowing them to sample and cache food quickly. Chipmunks also complicate protection efforts with their extensive burrowing habits, creating complex tunnel systems that can stretch up to 30 feet long and 3 feet deep underground. These burrows, which often have multiple, camouflaged entrances, allow them to access garden beds from below, bypassing simple perimeter fences.
Building an Impenetrable Defense
Physical exclusion is the most reliable method for protecting strawberries from chipmunks. The most effective material is hardware cloth, a galvanized wire mesh sturdier than standard chicken wire. A mesh size of 1/4-inch is recommended, as this small opening prevents chipmunks and other small rodents from squeezing through. This material must create a complete enclosure, addressing both above-ground and below-ground access points.
To prevent chipmunks from burrowing under the barrier, the hardware cloth must be buried around the perimeter of the strawberry patch. An “L”-shaped barrier is effective, where the mesh extends at least 6 to 12 inches vertically into the soil and then bends outward horizontally for another 6 to 12 inches. For raised beds, lining the entire bottom of the bed with 1/4-inch hardware cloth before adding soil prevents subterranean entry. Over the top of the patch, a cage or frame covered with the same mesh or bird netting must be secured tightly to the buried perimeter.
Using Scents and Tastes to Deter
While physical barriers are the primary defense, taste and scent repellents provide a secondary layer of protection. Repellents based on capsaicin, the compound that gives chili peppers their heat, are effective because they create an unpleasant taste experience without harming the animal. A homemade spray can be created using hot pepper or cayenne powder mixed with water and a few drops of dish soap, which helps the mixture stick to the fruit and foliage.
This capsaicin spray must be applied directly to the strawberry plants and fruit, requiring frequent reapplication, especially after rain or heavy watering. Scent-based deterrents, such as peppermint oil, garlic, or coffee grounds, can be placed around the perimeter of the patch. Chipmunks find these strong odors unpleasant, which discourages them from entering the immediate area. Commercial granular or liquid repellents often use similar ingredients or predator scents to create an odor barrier. Rotating the type of repellent used can help maintain effectiveness, as chipmunks can become accustomed to them over time.
Long-Term Yard Management for Prevention
Protecting the strawberry patch is only one part of a comprehensive strategy; managing the broader yard environment reduces chipmunk population pressure. Chipmunks are attracted to areas that provide both food and shelter, so eliminating these attractants is a long-term preventative measure. Removing debris, rock piles, and dense brush near the garden eliminates hiding and nesting spots.
Securing other food sources is important, especially bird feeders, which are a major attractant. Spilled birdseed should be cleaned up regularly, and feeders should be placed at least 15 to 30 feet away from the garden. Using chipmunk-proof feeders or switching to seeds like thistle, which chipmunks are less interested in, helps reduce their presence. For severe infestations, live trapping and relocation can be considered to reduce the local population, but gardeners must first check local regulations regarding wildlife relocation.