What Are the Best Companion Plants for Peppers?
Peppers grow best with marigolds, sweet alyssum, cilantro, spinach and lettuce. 11 plants in our chart pair well with peppers, mostly by deterring or trapping pests and attracting pollinators and beneficial insects; 3 of those pairings are research-supported.
| Plant | Why | Evidence |
|---|---|---|
| MarigoldsPest control | French marigold roots release a compound that suppresses root-knot nematodes, which also attack peppers. The effect is documented, but it is strongest when marigolds grow densely in the bed for a season before peppers; a few border plants do little. | Research-supported |
| Sweet AlyssumPollinators & beneficials | Sweet alyssum's tiny flowers feed hoverflies and parasitic wasps; hoverfly larvae eat the aphids that attack peppers. | Research-supported |
| CilantroPollinators & beneficials | Cilantro bolts in the heat just as peppers grow, and its small flowers feed hoverflies and parasitic wasps that control aphids. | Research-supported |
| SpinachSpace & timing | Spinach sown in early spring is harvested before peppers fill out, so the same space produces two crops. | Practical |
| LettuceSupport & shade | Pepper foliage gives lettuce partial afternoon shade, which slows bolting in early summer. | Practical |
| BasilPest control | Basil and peppers need the same warm, sunny conditions; basil is said to deter thrips and aphids, though evidence is limited. | Traditional |
| OnionsPest control | Onions fit between pepper plants, and their scent is thought to discourage aphids; the benefit is anecdotal. | Traditional |
| CarrotsSpace & timing | Carrots grow in the loose soil between pepper plants and root deeper than peppers, so the two share space with little competition. | Traditional |
| OreganoPollinators & beneficials | Oregano's low mat covers soil between pepper plants, and its flowers draw bees and small beneficial wasps. | Traditional |
| NasturtiumsPest control | Nasturtiums can pull aphids away from peppers as a trap crop; pull infested nasturtiums before aphids move on. | Traditional |
| ChivesPest control | Chives are a traditional aphid deterrent around peppers and take little space; the evidence is anecdotal. | Traditional |
Good companion plants for peppers, strongest evidence first.
What Should You Not Plant With Peppers?
Don't plant peppers near potatoes, corn, strawberries, fennel and black walnut. The conflicts come mainly from shared pests and diseases and allelopathy (plant chemicals that suppress growth); 3 of the 5 are research-supported and the rest are practical or traditional rules.
| Plant | Why | Evidence |
|---|---|---|
| PotatoesShared pests & disease | Potatoes share Verticillium wilt and potato virus Y with peppers; aphids spread the virus from potato plants to nearby peppers. | Research-supported |
| CornShared pests & disease | European corn borers and corn earworms both feed in pepper fruit; a nearby corn patch can raise their numbers. | Research-supported |
| StrawberriesShared pests & disease | Peppers host Verticillium wilt, a soil fungus that survives for years and kills strawberry plants. Don't grow strawberries near or after peppers. | Research-supported |
| FennelAllelopathy | Fennel is widely said to stunt peppers. Fennel extracts inhibit germination in lab tests, but garden-scale evidence is thin; its size and water use are the practical reasons to keep it apart. | Traditional |
| Black WalnutAllelopathy | Black walnut roots release juglone, and peppers are commonly reported to wilt and decline within the tree's root zone. | Traditional |
Plants to keep away from peppers.
Which Pepper Companion Claims Are Backed by Research?
6 of the 16 pepper pairings in our data are research-supported: marigolds, sweet alyssum, cilantro, potatoes, corn and strawberries. Of the rest, 2 rest on practical horticulture and 8 are traditional claims.
Research-supported pairings rest on documented biology: shared pathogens, pollination, nematode suppression or insects that feed on specific flowers. Practical pairings are plain logic about space, shade and timing. Traditional companions such as basil, onions, carrots and oregano are harmless to grow with peppers, but don't rely on them for pest control — row covers, crop rotation and regular checks do more.
How Should You Plant Peppers With Companions?
Space peppers about 18 inches (45 cm) apart and plant basil or onions between them; a row of oregano or sweet alyssum along the bed edge covers bare soil and feeds beneficial insects. Keep the pepper bed well away from sweet corn and potatoes.
Companions still need room of their own, so work out how many peppers and partner plants fit in a bed with the plant spacing calculator. Planting dates for peppers and their companions follow your local spring and fall frost dates, so warm-season partners go in together after the last spring frost, while cool-season fillers such as spinach and radishes use the bed before then.
Watering, feeding, light and harvest timing for peppers are covered in the bell pepper care guide.
Which Crops Share Companions With Peppers?
Tomatoes, eggplant and basil share companion plants or growing conditions with peppers, so their companion guides help plan the same bed or rotation.
- The guide to companion plants for tomatoes overlaps with this one: both crops grow well with marigolds, sweet alyssum and spinach; as members of the same plant family, the two should rotate together.
- The guide to companion plants for eggplant overlaps with this one: both crops grow well with marigolds, sweet alyssum and spinach; as members of the same plant family, the two should rotate together.
- The guide to companion plants for basil overlaps with this one: both crops grow well with chives, and basil is a good companion for peppers too.
To check peppers against every other plant at once, or test a whole bed plan, use the companion planting chart and garden checker.
Frequently Asked Questions
- What is the best companion plant for peppers?
- Marigolds are one of the best-supported companions for peppers. French marigold roots release a compound that suppresses root-knot nematodes, which also attack peppers. The effect is documented, but it is strongest when marigolds grow densely in the bed for a season before peppers; a few border plants do little.
- What should you not plant with peppers?
- Avoid planting peppers near potatoes, corn, strawberries, fennel and black walnut. The most important conflict is with potatoes: Potatoes share Verticillium wilt and potato virus Y with peppers; aphids spread the virus from potato plants to nearby peppers.
- Can you plant peppers and tomatoes together?
- Yes, peppers and tomatoes can share a bed; neither is known to help or harm the other. Both belong to the nightshade family (Solanaceae), so they share pests and diseases — rotate them together and don't follow one with the other.
- Does companion planting really work for peppers?
- Partly. 6 of the 16 pepper pairings in our data are backed by research, 2 are practical space or timing rules, and 8 are traditional. Flowers that feed beneficial insects and separating crops that share diseases have the strongest evidence.
- Can you plant hot and sweet peppers together?
- Hot and sweet peppers can grow side by side. They may cross-pollinate, but the cross only shows up in the seeds and in plants grown from them next year; this year's fruit keeps the heat and flavor of its own variety. Separate them only if you save seed.
Companion data: PlantoScan's own editorial compilation, written from general horticultural knowledge, plant pathology and published intercropping research. Evidence labels are our editorial judgment; results vary with climate, soil, variety and pest pressure.