10 Plants You Should Never Grow Next to Spinach, According to Horticulturists

Fennel

Fennel is a bad neighbor for many plants, and spinach is no exception. "It releases chemicals in the soil that stunt the growth of nearby vegetables," says Linda Langelo, horticulture specialist at Colorado State University. So while fennel certainly is delicious—and the idea of a verdant green edible garden is certainly enticing—it's best to grow it in its own space, far away from your spinach crop.

Strawberries

Strawberries are a delicious, juicy fruit that's easy to grow in a home garden—but they don't make good neighbors for spinach. "They would grow into the space where spinach is planted," says Langelo. "Plus, they use the same nutrients and water."

There are other concerns as well. "They harbor fungal diseases and pests that also affect spinach," says Ankit Singh, an assistant professor and horticulture educator at the University of Maine. "This can increase the chance of fungal leaf spot and soil-borne pathogens."

Pumpkins

Some plants make for bad neighbors just by virtue of their size and spread. "Pumpkins will grow vines to shade out spinach," says Langelo. "That's detrimental because spinach needs a good bit of sun every day."

Instead, find different real estate for your spinach. "Smaller plants like spinach should be grown in other parts of the garden to avoid being shaded out and overgrown by these plants," says Ward Dilmore, founder and head landscape designer at Petrus Landscaping.

Sunflowers

"Sunflowers aren't good companions for many plants," says Langelo. Why? These flowers may look lovely, but they can also release toxins that will inhibit the growth of nearby vegetables.

"Spinach grown near sunflowers may exhibit poor germination or stunted growth due to these allelopathic compounds," adds Singh.

Tomatoes

We love tomatoes, but they take up a lot of real estate.

"They should be planted in their own part of the garden," says Dilmore. "By the middle of the summer, tomatoes will get very large and shade out any undergrowth." Great if you're trying to kill weeds, but bad for spinach, which thrives in full sun.

Mint

Mint can be delightful—when it's properly contained. These aromatic herbs may smell good, but they can spread very aggressively and quickly take over a garden. That's bad news for spinach, which may have its own growth hindered as a result.

"The best place for mint is likely a container, which can keep its growth under control," adds Dilmore.

Beets

Beets are great for humans, but spinach won't find the same nutritional appeal. In fact, it's nutrients that are the problem, as these two are part of the same plant family and thus compete for similar nutrients.

"Planting them nearby can lead to poor nutrient uptake for both crops, and a higher risk of shared diseases, like downy mildew," says Singh.

Potatoes

Potatoes are heavy feeders and need a lot of nutrients to grow. Unfortunately, that means they can deprive spinach of what it needs to thrive.

“Potatoes can stunt spinach growth due to nutrient competition, especially nitrogen; they also attract similar pests, like leafminers," says Singh.

Sage

Sage can grow into a small shrub, which is bad news for spinach. "It will shade out spinach and has competing root systems for nutrients," says Dilmore. Instead, he recommends planting herbs in a separate part of the garden so they're easier to maintain and control.

Kale

Kale, like potatoes, is a heavy feeder, and will pull nitrogen out of the soil—which spinach needs in order to grow. Planting the two together as neighbors can also "an increased risk of aphid infestations," says Singh.