Potatoes repay a little planning around what grows beside them. Potato plants need full sun, soil with a pH of 5.0–6.0, 12 inches of space and 70–120 days to reach maturity, so their neighbours need to suit the same bed and the same season. This guide lists the companions for potatoes from our crop data, how each one is thought to help, and which close relatives to keep apart.
There are 5 companions listed for potatoes here: beans, corn, cabbage, marigolds, horseradish. Companion planting is traditional garden practice rather than proven science, so benefits below are described in those terms — what gardeners have long said and done. Potatoes are in the Solanaceae family, need moderate water, and are sown directly where it is to grow; it is frost-tolerant, so light frosts will not kill it, though a hard freeze still can. Check any pairing first with the companion-planting finder.
Best companion plants for potatoes
| Companion | Why it is grown with potatoes |
|---|---|
| Beans | Legumes that fix nitrogen from the air into the soil through their roots, which can benefit a hungry neighbour such as potatoes. |
| Corn | Grows tall and can give light shade or a windbreak. Plant on the north side so it does not shade potatoes. |
| Cabbage | Grows low and broad, shading the soil. Suits the same rich, moist bed as potatoes but needs its own space. |
| Marigolds | Grown as a border or dotted through the bed; roots are traditionally said to discourage some soil pests, and flowers attract beneficial insects. |
| Horseradish | Traditionally grown in a corner, where its strong roots are said to deter some pests. Spreads vigorously, so keep it contained. |
Marigolds work best as a border around the potatoes bed rather than scattered at random. A ring of marigolds marks the bed edge, flowers for months, and is traditionally said to discourage some soil pests through its roots. They tolerate the same full sun as potatoes, and one sowing covers the whole season if you deadhead spent flowers.
How companion planting works
Companion planting works through four overlapping mechanisms.
Pest confusion. Many pests find their host plant by scent. Strong-smelling companions such as onions, basil and aromatic herbs are traditionally said to mask that scent, so the pest passes by. It is a delaying effect, not a barrier.
Pollinator and beneficial-insect attraction. Several companions here flower — marigolds — drawing pollinators and beneficial insects in. Let a few flower.
Nitrogen fixing. Nitrogen fixing applies directly here: potatoes' companions include a legume, which captures nitrogen from the air into the soil.
Ground cover and root layers. No companion here is a ground-cover plant, so mulch does that job instead. Deep roots beside shallow ones also compete less for water and nutrients.
None of this replaces the basics. Spacing, watering, rotation and weekly inspection matter more than any pairing.
Plants to avoid near potatoes
The plants to keep away from potatoes are its own relatives. Potatoes belong to the Solanaceae family, and plants in the same family share the same pests and diseases — here, Colorado potato beetle, aphids, wireworms — so problems pass easily between them and build up in the soil.
| Plant to avoid | Why |
|---|---|
| Tomatoes | Same Solanaceae family; shares pests such as Colorado potato beetle, aphids, wireworms. |
| Bell Peppers | Same Solanaceae family; shares pests such as Colorado potato beetle, aphids, wireworms. |
| Hot Peppers | Same Solanaceae family; shares pests such as Colorado potato beetle, aphids, wireworms. |
| Eggplant | Same Solanaceae family; shares pests such as Colorado potato beetle, aphids, wireworms. |
Keep these relatives in a different bed and rotate the Solanaceae family to fresh ground each year. Others in the same family in our crop data include Jalapenos, Habaneros, Chili Peppers, Roma Tomatoes, Cherry Tomatoes, Heirloom Tomatoes, Russet Potatoes, Red Potatoes, Petunias.
Planting layout and spacing
Give potatoes their full spacing of 12 inches between plants. Crowded potatoes mean poor airflow, more disease and smaller harvests, and no companion plant compensates for it. Work out how many plants fit your bed with the plant-spacing calculator or the square-foot garden planner.
Plant companions in the spaces the spacing leaves, not instead of it. Low companions go in the gaps and along the bed edges; taller ones go at the north side so they do not shade the potatoes; scented herbs go closest to the crop, dotted through the row.
Potatoes are sown directly where it is to grow, so sow where they are to grow and thin to the final spacing once seedlings are up. Germination takes 14–28 days. Potatoes need full sun and soil with a pH of 5.0–6.0. Water needs are moderate, so keep the soil consistently moist with deep, regular watering rather than a light daily sprinkle, and mulch thickly to hold moisture in. The watering calculator gives a starting point for your bed size. Expect 70–120 days from sowing to maturity.
Common problems and fixes
The pests most often reported on potatoes are Colorado potato beetle, aphids, wireworms, flea beetles. Companions may reduce pressure, but they do not prevent them — inspect leaf undersides and new growth weekly and act while numbers are low.
| Problem | What you see | First fix |
|---|---|---|
| Colorado potato beetle | Striped beetles; orange egg masses on leaf undersides. | Hand-pick; crush egg masses; rotate yearly. |
| Aphids | Sap-sucking insects on new growth; leaves curl. | Wash off with water; encourage ladybirds. |
| Wireworms | Thin orange-brown larvae bore into roots and tubers. | Rotate; remove larvae while digging. |
| Flea beetles | Tiny jumping beetles chew small holes in young leaves. | Fine mesh or row cover on young plants. |
Colorado potato beetle
Hand-pick adults and larvae, crush the orange egg masses, and rotate yearly.
Aphids
Wash them off with a strong jet of water and leave ladybirds and lacewings alone to eat them.
Wireworms
Avoid planting after digging up grassy ground, and rotate the bed.
Flea beetles
Cover young plants with fine mesh or row cover until they are strong.
Unsure what you are seeing? Try the pest-identifier helper or the plant-disease checker. Remove badly affected leaves and rotate the Solanaceae family next year.
Frequently asked questions
What is the best companion plant for potatoes?
The most widely recommended companion is beans. Legumes that fix nitrogen from the air into the soil through their roots, which can benefit a hungry neighbour such as potatoes.
What should not be planted near potatoes?
Avoid other members of the Solanaceae family, including Tomatoes, Bell Peppers, Hot Peppers. They share the same pests and diseases as potatoes, so problems move easily between them. Rotate the family to a fresh bed each season.
Can I plant potatoes with corn?
Yes. Corn is on the companion list for potatoes. Grows tall and can give light shade or a windbreak. Plant on the north side so it does not shade potatoes.
How far apart should potatoes and their companions be planted?
Space potatoes plants 12 inches apart, and put companions in the gaps, along the edges and at the ends of rows. The plant-spacing calculator works out how many plants fit your bed.
Does companion planting replace pest control?
No. It may reduce pest pressure, but it does not replace inspection, spacing, watering, rotation and good airflow. Check plants weekly and act early.