The Best Companion Plants For Cucumbers And The Ones to Avoid

Cucumbers are one of the hardest working vegetables in the vegetable garden (right behind tomatoes). Every year we grow cucumbers for all kinds of canning recipes, from pickles to relish and everything in between. We’ve found through the years what works and what doesn’t when it comes to growing a bounty of cucumbers. The best trick is adding companion plants for cucumbers – companions can help improve yield, taste, and the general health of your cucumber plants.

The benefits of companion planting in your garden

Companion planting is a great way to deal organically with those unwanted pests in your garden. Using companion plants allows us to avoid using pesticides which we all know are incredibly harmful to soil and beneficial insects like bees. Companion planting offers many other incredible benefits for the garden:

• Repels insect pests. All kinds of garden pests can attack vegetable gardens: aphids, cabbage worms, cucumber beetles, flea beetles, Mexican bean beetles, squash bugs, carrot flies, and cabbage moths. Many companion plants help repel specific pests and should be planted near specific crops as natural non-chemical pest control. 
• Higher yield: The companion planting of flowers will help attract beneficial pollinators like bees.
• Attract beneficial insects by interplanting your garden with companion flowers. You will encourage beneficial insects like parasitic wasps, ladybugs, and lacewings to hang around your garden.
• Encourage faster growth and better taste. Many companion plants release specific chemicals that encourage speedier growth or better taste in the plants around them.
• Provide ground cover. Plants that spread low across the ground serve as a blanket over the soil and help keep the environment moist. 

Learn More: Check out our full guide to Companion Planting Vegetables.

How to Plant Cucumbers

Cucumbers (Cucumis sativus )need a long growing season – most varieties are ready to harvest around 50-70 days after planting the seeds. But, the soil needs to be 70 degrees for cucumber seeds to germinate, and they’re very susceptible to frost damage. For these reasons, I don’t recommend planting (or transplanting) them outside earlier than two weeks after the last frost date.

If you live in an area with a short growing season, that timing can be a little tricky, so I recommend starting the seeds indoors about three weeks before you want to transplant them into the ground.

Cucumbers are an incredibly easy vegetable to grow, even for first-time gardeners.

Tips for growing & harvesting cucumbers

• Your plants will need at least 1 inch of water per week, and even more when it’s really hot. Using a soaker hose to water close to the ground will reduce evaporation and prevent water from getting on the leaves, which can cause leaf diseases.
• Plan a watering routine that’s consistent because inconsistent watering causes bitter-tasting cucumbers.
• If you want to use trellises to train your vines to grow vertically, set them up before your plants need them, so you avoid damaging your seedlings or vines.
• Mulch the ground to retain more moisture.

You can harvest your cucumber when they:

• Have a nice uniform green color – the color may vary slightly so check your seed packet for more details. If they’ve turned yellow, they’re past their peak.
• Are firm to the touch
• Are the right size – at least 2 inches long for pickling varieties and 7-8 inches for slicing varieties. Check your seed packet for more details.
• Have girth – ripe cucumbers are about 1.5” in diameter.

See: How To Grow Cucumbers (detailed post outlining everything you need to know to grow healthy cucumber plants)

The Best Companion Plants To Grow With Cucumbers

Here is the list of companions, below we have details to explain why each plant makes a good pairing with cucumbers.

• Beans & Peas
• Sweet Corn
• Pepper Plants
• Radishes
• Asparagus
• Lettuce
• Carrots
• Tomato plants
• Nasturtiums
• Marigolds
• Sunflowers
• Dill

The best vegetable companion plants for cucumbers

Here is a quick list of the plants that do well interplanted with cucumbers. In the remaining article, we go through all the beneficial plants to explain what each plant provides and why it is a great companion for cucumbers.

Beans & Peas

Legumes like peas, bush beans, and pole beans make great companion plants for cucumbers. They make excellent companions as the bean plants add much-needed nitrogen to the soil. Increasing nitrogen levels in the soil help the cucumber plants thrive. In addition, pole beans and green beans are great for trellising behind cucumbers. Allow the cucumbers to trail in front of the trellised peas or beans.

Beans & peas produce best when planted in full sun. They require fertile well-draining soil with lots of compost added at the start of the season.

Sweet corn

Corn and cucumbers form a symbiotic relationship; Sweet corn makes a natural trellis for the cucumber vines to climb. In addition, the cucumber vines provide a living mulch along the base of the corn stalks keeping the soil moist and weeds at bay. Corn plants are heavy feeders and require rich fertile well-drained soil to produce. Plant cucumbers at the edges of the corn patch and allow them to trail and climb Be sure to choose smaller varieties of cucumbers to prevent toppling the corn stalks from heavy fruit.

pepper plants

Peppers and cucumbers share similar needs for growing conditions, so they work well planted as a pair. It’s a good idea to grow the cucumbers vertically up a trellis or support while planting the peppers plants in front. Peppers and cucumbers do not share a number of common pests and this also makes it a good companion plant.

radishes

Radishes may help deter cucumber beetles, acting as a trap crop for flea beetles. In addition, root vegetables like radish are well planted with cucumbers because their roots do not interfere with each other.

lettuce

Lettuce plants have very shallow root systems and co-exist quite happily with cucumbers as their root system does not interfere with each other. The plant acts as a living mulch under trellised cucumbers and helps prevent the soil from drying out.

Carrots

Carrots and cucumbers share the same growing conditions and pair well in a garden bed. Since cucumbers only send down one large taproot, planting carrots in front of the vines will not negatively impact root vegetables like carrots. The same can be said for root crops like beets.

Flower companion Plants for Cucumbers

The three flowers mentioned below get planted aggressively in my vegetable garden every year. I would not garden without them. They work exceptionally well as companions for cucumbers.

nasturtiums (trap crops) make good companion plants

Nasturtiums make good companion plants with cucumbers because they act as a trap crop for pests like flea beetles and aphids. The vines and flowers also look lovely intertwined with cucumber vines.

Plant nasturtium seeds outdoors in the spring after the last frost in your region. Nastriutums enjoy full sun but will tolerate light shade. Shade may deter blooming but lack of blooms will not impact their ability to deter pests. The plants can also help improve the taste of your cucumbers.

See: How to grow nasturtiums.

marigolds

Marigolds look lovely planted in the vegetable garden, but they provide more than good looks. The plant makes an excellent companion plant that helps deter pests away from fruit vines and root vegetable crops. For example, marigolds help deter aphids, Japanese beetles, and spotted cucumber beetles. The strong scent of marigolds acts like bug spray for the cucumber plants. If you continually deadhead marigolds they will flourish and bloom all through the season right up until the first frost.

See: The Best Companion Plants for Marigolds.

sunflowers

You can use sunflower as natural trellises for vining cucumbers. Be sure to pick smaller growing cucumbers, like pickling cucumbers, to prevent the stalks from collapsing from heavier types.

Plant sunflowers in full sun with well-drained soil. You can direct seed Sunflowers in the spring after the last frost. Sunflowers are also great for bees and birds in the fall when other flowers and food sources have stopped blooming.

See: How to Grow Sunflowers.

Herb Companions For Cucumbers

Dill

Dill will help cucumbers by attracting beneficial predatory insects like ladybugs, green lacewings, parasitic wasps, hoverflies, spider mites, and aphid midges. That’s a lot of general pest protection.

See: Dill Plants: How To Grow, Harvest & Use Them.

Plants you should not grow with cucumbers.

The worst cucumber companion plants for cucumbers share similar diseases and or will negatively affect the taste of the cucumbers.

melons

The same insects that like to infest melons also love to invade cucumber plants. Planting cucurbits together creates a monoculture, and diseases and pests thrive in monocultures. Avoid planting melons, squash, and pumpkins with your cucumber plants.

potatoes

Cucumbers can encourage potato blight if the environment is just right. Once potato blight takes hold in your garden, it’s challenging to control, so be sure to plant your cucumbers are far away as possible from your potato beds. Potatoes and cucumbers also share similar fungal diseases.

Brassica family

Brassicas like cabbage, kale, broccoli, and Brussels sprouts make poor pairings in the vegetable garden. They are very thirsty hungry plants that will deplete the resources required to grow both a brassica and a cucumber in the same bed. Brassicas are challenged with infestations of cabbage loopers and planting cucumbers nearby is an invitation for the cabbage loopers to also infest the cucumbers plants.

aromatic herbs

Aromatic herbs like oregano, basil, sage, bay, summer savory, and mint can impart an off-flavor to the cucumbers. Unfortunately, Sage can also stunt the growth of your cucumber plants.  It’s a good idea to keep the bulk of your herb garden away from your cucumber plants.

Cucumbers and their best companion Plants

You can see from this list that there are numerous plants that can be grown side by side with cucumbers. Plants that provide excellent pest control, help improve the soil and taste of the fruit as well as protect the plants from environmental stresses. We love to companion plants in our garden to add diversity to our beds which helps control environmental stresses like diseases and pests.

If you haven’t ever companion planted in your garden before I urge you to give it a try this year, even if only a few plants in a few beds. We would love to hear what your results are so tag us on social media, or drop us a line. We very much love seeing other folk’s gardens and hearing about what works for them. If you have any suggestions or comments we welcome you to leave them below.

Cheers to an excellent growing season!

Looking For More Companion Gardening Information?

• Companion Plants for Pumpkins – A Gardeners Guide!
• Rhubarb Companion Plants: A Very Detailed Guide.
• Beet Companion Plants
• A Guide to The Best Eggplant Companion Plants
• Companion Plants for Zucchini For Better Yields
• Vertical Vegetable Gardens
• Companion Plants for Asparagus
• Canning Tomatoes Whole – The Quick and Easy Cold Pack Method