Brassicas are heavy feeders, just like tomatoes. When planted too close to each other, they compete for the same nutrients, especially nitrogen, which can stunt the growth of both plants. Additionally, brassicas can release chemicals
Fennel is known for its allelopathic properties, meaning it releases chemicals into the soil that can inhibit the growth of nearby plants, including tomatoes. The chemicals from fennel can stunt the growth of tomato plants
While corn might seem like a harmless neighbor, it attracts some of the same pests as tomatoes, particularly the corn earworm and tomato fruitworm. If planted too close together, these pests can easily move from corn to tomatoes
Young dill plants can actually be beneficial to tomatoes by repelling pests, but as dill matures, it can inhibit the growth of tomato plants. The roots of mature dill can release substances that are harmful to tomatoes, and its tall
Tomatoes and potatoes belong to the same plant family, the Solanaceae, and share many of the same diseases, such as blight and early blight. Planting them close together increases the risk of disease spreading from one plant to the other.
Walnut trees produce a chemical called juglone, which is toxic to many plants, including tomatoes. Juglone can inhibit the growth of tomatoes, causing wilting, yellowing leaves, and even death in severe cases.
Like potatoes, eggplants are also members of the Solanaceae family and share similar diseases with tomatoes. When planted too close together, they can easily transmit diseases like blight and pests like the Colorado potato beetle.
Kohlrabi is another plant that can inhibit the growth of tomatoes. This brassica can compete with tomatoes for nutrients and space, and its dense growth habit can shade out smaller tomato plants, reducing their access to sunlight.
Although peppers are often grown alongside tomatoes, they can compete for the same nutrients, particularly when grown in close proximity. Both tomatoes and peppers are heavy feeders, and planting them too close together
Rosemary is a robust, aromatic herb that prefers dry, well-drained soil, which contrasts with the needs of tomatoes, which thrive in consistently moist, nutrient-rich soil. Planting rosemary near tomatoes can create a conflict in watering needs