Being picky about what you grow alongside your easy-to-cultivate cucumbers can mean the difference between a meager or magnificent harvest. The best cucumber companion plants help deter pests and don't compete with this member of the gourd family for water or nutrients. The worst neighbors do just the opposite.
But what garden plants fare well alongside these vigorous vines, and which ones should you steer clear of?
Best Cucumber Companion Plants
Some of the most popular plants to grow alongside cucumbers include:
- Legumes (peas, beans, lentils)
- Root vegetables (radishes, beets, carrots, garlic)
- Select flowers (marigolds, nasturtiums, sunflowers)
- Select herbs (dill and oregano)
Learn more about why these are the best cucumber companion plants and why you should not grow incompatible companions such as potatoes, sage, mint, and melon.
What Is Companion Planting?
Companion planting is the practice of growing different species together based on their ability to enhance one another's development, offer some form of pest protection, or other advantages.
Sometimes it is a matter of choosing plants with different growth habits that do not compete with one another for space, or it can mean choosing companions with varying nutrient needs to use soil efficiently. Ideally, companion plants help ward off destructive insects, making garden pest management easier.
Some companion planting simply involves common sense—making sure that taller plants don't provide too much shade to low-growing plants, for instance. Strategic companion planting is especially important in small gardens or wherever careful space planning is needed.
Benefits of Companion Planting
Seasoned gardeners swear by companion planting because it increases the health and productivity of crops like cucumbers. The benefits of selecting appropriate companion plants for cucumbers or any other plant include:
- Naturally repelling insects
- Deterring certain diseases
- Minimizing competition for space, nutrients, or water
- Can add beneficial nutrients to the soil
- Providing stability for climbing species
- Tall plants can provide shade for ground-growing, shade-loving species
Best Companion Plants for Cucumbers
Various vegetables, flowers, and herbs make excellent cucumber companion plants. These include:
- Peas, corn, beans, and lentils: These plants' root systems increase nitrogen in the soil, which will benefit your cucumber plants. Mature corn stalks also provide natural support for climbing cucumbers and provide much-needed shade in sun-scorched spaces.
- Radishes, beets, carrots, and onions: These root vegetables work well with cucumbers because they do not spread and compete for space; most of their growth occurs beneath the soil. Conversely, cucumbers have one long taproot and many shallow roots that grow and spread close to the soil surface, and the fruits grow above ground. Root vegetables and cucumbers both thrive in well-tilled soil. Radishes help repel cucumber beetles.
- Marigolds and nasturtiums: These flowers help repel beetles, thrips, and other destructive insects that can devastate your cucumber crop.
- Sunflowers: These tall, sturdy flowers can be natural trellises for climbing cucumber vines when space is at a premium. It's best to pick a lightweight cucumber species to prevent them from becoming too heavy for your sunflower stalks. Plus, sunflowers are pollinator superheroes, and studies show these types of plants can increase cucumber crop yields.
- Oregano and dill: These herbs repel insect pests, and dill attracts beneficial predatory insects to the garden to help rid it of pests. Many enthusiasts swear by dill for improving the flavor of cucumbers.
- Garlic: Studies show garlic can promote cucumber growth and decrease the chances of plants developing fusarium wilt by affecting the soil microbiome structure.
Worst Companion Plants for Cucumbers
Steer clear of the following vegetables, herbs, and fruits when selecting your cucumber companion plants.
- Potatoes: These heavy-feeding tubers compete with cucumbers for nutrients and water and can be prone to blight.
- Sage: This aromatic herb can stunt the growth of cucumbers, and its strong fragrance could affect its subtle flavor.
- Mint: Most varieties of mint are overly aggressive in garden beds and can infringe on the space for cucumbers and steal their nutrients.
- Melons: These fruits attract insect pests that feed on cucumbers.
- Fennel: If you're a fan of this licorice-scented vegetable, it's best to find a space away from other garden vegetables, not just cucumbers. It secretes substances from its roots that can inhibit the growth of other plants.
Cucumber Mosaic. University of Wisconsin Division of Extension
Companion Planting. Cornell University Extension Service
Montoya, John E., et al. ‘Pollinator-Attracting Companion Plantings Increase Crop Yield of Cucumbers and Habanero Peppers’. HortScience, vol. 55, no. 2, Feb. 2020, pp. 164–69. journals.ashs.org, https://doi.org/10.21273/HORTSCI14468-19.
Your Own Vegetable Garden of Eden: Companion Planting. Cornell University Master Gardeners.
Ali, Ahmad, et al. ‘Garlic Substrate Induces Cucumber Growth Development and Decreases Fusarium Wilt through Regulation of Soil Microbial Community Structure and Diversity in Replanted Disturbed Soil’. International Journal of Molecular Sciences, vol. 21, no. 17, Aug. 2020, p. 6008. PubMed Central, https://doi.org/10.3390/ijms21176008.