The practice of companion planting involves growing different crops near each other to confer mutual benefits, such as natural pest control or improved nutrient uptake. The compatibility of tomatoes and strawberries is a frequent inquiry. While both are popular home garden crops, their close proximity is generally discouraged due to fundamental biological and resource conflicts.
Shared Disease Vulnerability
The primary risk in planting tomatoes and strawberries together is their shared susceptibility to specific soilborne fungal diseases. Both plant species are hosts for Verticillium wilt. The fungi invade the plant’s vascular system, blocking the flow of water and nutrients, which ultimately causes the leaves to wilt and the plant to decline.
This pathogen is problematic because it can survive in the soil as tiny, dormant structures called microsclerotia for up to 14 years. Planting a tomato near a strawberry plant significantly increases the concentration of the pathogen in the soil, raising the risk for both crops. If one plant becomes infected, the close proximity allows the fungal spores to spread easily, increasing the likelihood of crop failure in both species.
Differing Resource Needs
Beyond the risk of shared disease, tomatoes and strawberries have distinctly different requirements for soil chemistry, nutrient balance, and water management. Tomatoes are heavy feeders that demand high levels of nitrogen and require consistent, deep watering to support their extensive root systems and large fruit production. The optimal soil pH range for tomatoes is slightly acidic, generally between 6.0 and 6.8.
In contrast, strawberries prefer a more intensely acidic soil environment, thriving in a range of 5.3 to 6.5. They are shallow-rooted plants that require moderate, consistent moisture near the soil surface, not the deep saturation needed by tomatoes. High nitrogen fertilization, which benefits tomatoes, can be detrimental to strawberries, leading to excessive leaf growth and soft, poor-quality fruit.
The difference in plant structure also creates competition. The tall, dense tomato plants can easily shade the low-growing, sprawling strawberry plants, hindering the strawberries’ access to the full sun they require.
Successful Companion Options
Since tomatoes and strawberries are poor neighbors, gardeners should focus on pairing each crop with species that offer genuine support and address their specific needs.
Tomato Companions
Beneficial companions for tomatoes help deter pests and improve soil health.
- Herbs like basil, which may help deter pests such as the tomato hornworm.
- Borage, which attracts beneficial pollinators and may enhance fruit quality.
- Marigolds, which repel nematodes.
- Bush beans, which fix nitrogen into the soil.
Strawberry Companions
Excellent companion options for strawberries do not compete for shallow nutrients and offer pest protection. Borage is a beneficial pairing, as it is believed to improve their flavor and vigor. Plants with strong scents, such as onions and garlic, deter destructive pests. Bush beans are also a good fit, as they enrich the soil by adding nitrogen.