Companion planting involves strategically placing different plant species near each other to create a mutually beneficial environment in the garden. For strawberries, this technique can significantly improve their health, yield, and flavor while providing a natural defense against pests and diseases. The right plant neighbors contribute nutrients, attract beneficial insects for pollination, and regulate soil conditions. Understanding which plants support strawberries is the first step toward a productive and ecologically balanced strawberry patch.
Plants That Boost Strawberry Growth
Specific companion plants can improve a strawberry patch’s overall vigor and fruit production. Borage, for instance, is a highly effective companion, attracting a variety of pollinators like bees, which is crucial for developing larger, higher-quality berries. Borage is also thought to enhance the flavor of the fruit and may mine trace minerals from deeper soil layers, making them available to the shallow-rooted strawberries.
Legumes, such as bush beans or clover, contribute to soil fertility by fixing atmospheric nitrogen into a usable form through a symbiotic relationship with rhizobia bacteria in their root nodules. While the nitrogen is primarily used by the bean plant, the roots and nodules release nitrogen back into the soil as they decompose, which benefits the nitrogen-loving strawberries. Low-growing greens like lettuce and spinach serve as an effective living ground cover. Their dense foliage helps suppress weed growth and retains soil moisture, greatly reducing competition for the shallow-rooted strawberry plants.
Plants That Deter Pests
Aromatic herbs and bulbs are effective at protecting strawberries by repelling or confusing common garden pests. Members of the Allium family, including garlic and onions, release sulfur compounds that create a strong scent barrier, deterring slugs, snails, and aphids. Garlic is noted for its fungicidal properties, offering protection against fungal issues like powdery mildew and gray mold, which can affect strawberry plants.
Marigolds are a recognized companion plant for managing microscopic soil pests. Specific varieties, such as French marigolds, release chemical compounds called thiophenes from their roots that are toxic to root-knot nematodes, which damage strawberry roots and stunt growth. Thyme, a low-growing herb, contributes to pest control by emitting aromatic compounds that repel various insects and by attracting beneficial predatory insects, such as hoverflies, whose larvae consume aphids.
Plants That Must Be Avoided
Certain plants must be avoided near strawberries due to the risk of disease transmission or intense resource competition. The most significant threat comes from members of the nightshade family (Solanaceae), including tomatoes, potatoes, eggplants, and peppers. These plants are often symptomless carriers of Verticillium wilt, a soil-borne fungus that can persist in the soil for many years and cause the sudden wilting and collapse of strawberry plants.
Other plants pose a risk through nutrient depletion or physical competition. Members of the cabbage family (Brassicas), including broccoli, cauliflower, and kale, are heavy feeders that compete intensely with strawberries for available nutrients and moisture in the soil. This competition can result in stunted growth and reduced yields for both plant groups. Plants that sprawl or have aggressive root systems, such as corn or certain melons, should also be kept away, as they can quickly overshadow the low-growing strawberries, blocking sunlight and depleting soil resources.