11 Plants That Spell Trouble When Grown with Tomatoes, Says Expert Gardener

Tomatoes They're among the most favored vegetables for home gardens due to their appeal. Tomatoes are tasty, healthy, and simple to cultivate provided you supply plenty of sunlight and rich soil. To get the best yield from your tomato plants, consider planting compatible species nearby.

Variety in the garden can assist with improving soil quality, decreasing pest problems, and suppressing weed growth. attract beneficial pollinators . However, while clever vegetable garden companion planting Additionally, referred to as interplanting or intercropping, this technique can enhance your tomato yield; however, certain other pairings might decrease your production.

We consulted with an expert to learn which plant types may not be ideal as companions for tomatoes and the reasons behind this.

Meet the Expert

Susan Scheufele , Dr. PhD serves as the Production Agriculture Leader in the UMass Extension Vegetable Program.

Broccoli

Broccoli and other members of the Brassica family require substantial nutrients, making it ideal to grow them separate from tomatoes to avoid inhibiting their development.

"When thinking about interplanting or companion planting near tomatoes, it’s advisable to avoid growing plants that will compete intensely with them for sunlight, water, or nutrients," says Susan Scheufele, an educator from the UMass Extension Vegetable Program.

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Cabbage

Cabbages are significant consumers of nutrients and require ample nourishment. To prevent competition between these cruciferous vegetables and tomatoes for essential resources, think about cultivating cabbages in another part of your garden area.

Sweet Corn

Scheufele does not suggest planting sweet corn alongside tomatoes because the taller corn plants may block sunlight from reaching the tomatoes.

"Corn requires substantial nutrients and has deep roots, which means it might deplete essential elements needed by tomatoes, potentially harming either the corn or tomato plants," she explains.

Furthermore, the tomato fruitworm, also referred to as the corn earworm, enjoys feeding on both types of vegetables. In case of an outbreak, this pest has the potential to decimate both crop varieties significantly.

Cucumbers

Although cucumbers have a lower profile, trail along the ground, and have shallow roots, Scheufele suggests they may not make the best companions for tomato plants.

They require ample sunlight and warmth to flourish," she explains. Planting cucumber vines too near to robust, towering tomato plants might result in excessive shading for the cucumbers.

Eggplants

Scheufele advises against growing other Solanaceous plants such as peppers or eggplants close to tomatoes. He explains that these crops have comparable growth patterns and attract many of the same pests because they belong to the same plant family.

Species of nightshade plants can also fall victim to fungal infections such as blight. Should your eggplants contract this condition, it is likely to transmit to nearby tomato plants.

Fennel

Several research findings indicate that growing fennel alongside tomatoes might lead to decreased yields. This occurs because various varieties of fennel tend to be taller than tomato plants, thereby blocking sunlight for those requiring ample light and warmth. According to Scheufele, opting for shorter, fast-maturing herbs such as parsley could be more beneficial. cilantro , instead.

Peppers

Bell peppers belong to the nightshade family just like tomatoes do, which means they might draw similar pests and diseases. To be safe from potential issues, it’s best to grow them in a different garden bed.

Potatoes

If you're looking to avoid potato plants contaminated with bacterial wilt or other fungal problems spreading Diseases can affect your tomato plants. In the ground, ensure these two solanaceous plants are placed in separate vegetable patches.

Sunflowers

Sunflowers can serve as useful and attractive boundary plants placed around a veggie garden to draw in helpful pollinators and deter certain pests.

Nonetheless, these plants are not ideal choices to grow right next to tomatoes. Due to their tall stature, they might shade the tomato plants, which require ample sunlight.

Scheufele suggests planting low-growing, short-season flowers like sweet alyssum or nasturtium Plant the seeds simultaneously with the tomato seedlings. This ensures they'll have ample access to light to establish themselves before the tomatoes become dense and shaded.

Sweet alyssum offers the additional advantage of drawing beneficial insects such as syrphid flies, lady beetles, parasitic wasps, and predatory beetles and bugs," explains Scheufele. "In contrast, certain flowers like nasturtiums emit powerful fragrances that can disorient insect pests, thereby reducing their ability to locate their host plants.

Sweet Potatoes

While sweet potatoes may not belong to the nightshade family, similar to regular potatoes, they are still not ideal companions for large, leafy tomato plants.

Scheufele notes that despite being low-growing, trailing plants with an extended growing period, these varieties might not produce numerous tubers. Additionally, the tubers could turn out small if cultivated in areas with limited sunlight.

Black Walnut Trees

Black walnut trees release a substance named juglone into the nearby soil. Plants from the nightshade family, such as tomatoes, have been found to be susceptible to this compound.

Naphthalene wilting may result in deteriorated health, unsatisfactory yields, and ultimately, the demise of the plant.

Read the initial article on The Spruce