Stop Planting Cucumbers Next To Potatoes In The Garden. Here's Why

It might be tempting to stuff a whole produce aisle into your garden beds, but some plants make for nasty neighbors. Overall, the nightshade family and the squash family just don't get along. While they might not seem obvious, potatoes (Solanum tuberosum) are technically nightshades, and cucumbers (Cucumis sativus) are a type of squash. Therefore, cucumbers are one of the plants you should never grow next to potatoes in the garden for a few reasons. Mostly it's because they will compete for the same resources, and together they can create conditions that open the door to disease.

Cucumber vines greedily soak up massive amounts of water, which can leave your slow-sipping potatoes high and dry. In a catch-22, watering too much might drench your potatoes, leading to rotten or malformed tubers. Even if you can strike the right balance of moisture, cucumbers and potatoes will compete for root space and nutrients in the soil, and if both plants still manage to thrive, their growth patterns can lead to fungal issues for each other.

Both potatoes and cucumbers are heavy feeders, which means that they require and abundance of nutrients in the soil to thrive. Cucumber plants prefer generous levels of potassium and phosphorous with slightly less nitrogen – and potatoes want exactly the same thing. It's challenging enough to keep these two species satisfied on their own, but when they're planted together, they can quickly deplete the soil of nutrients. Ultimately, they'll weaken each other and leave you with some pretty poor soil next season, especially if they're grown in the same spot year after year.

Both plants can suffer in this arrangement, but potatoes might get the shadier end of the deal — literally. As cucumber vines trail over the ground, they can block sunlight for the potato plants. Even if they're grown on a trellis, the wrong placement can cast shade over your spuds. Potatoes can often get by with at least six hours of full sunlight per day, so the shade from cucumber leaves might not be a catastrophe in and of itself. However, the high humidity and lack of airflow will leave potatoes vulnerable to blight, which can then spread to your cucumbers as well.

For better results, plant potatoes next to spinach, garlic, chives, or nasturtiums. Marigolds, sunflowers, beans, and corn will make good cucumber companion plants that you can rely on for healthy crops. If you must plant them in the same garden bed, make sure they're at least 3 feet apart, and train the vines on a trellis to grow big, healthy cucumbers in the garden without shading or overtaking your potatoes. When watering, aim for the base of the plants to avoid wetting the leaves and encouraging fungal growth.