I plant peppers with basil, marigolds, nasturtiums, borage, and onions as my top five companions, and I avoid tomatoes, potatoes, eggplant, and fennel because they share diseases, pests, or chemically stunt peppers. This quick list of companion plants for peppers gives the neighbors to plant and the ones to keep out of the bed so you can act this weekend.
Best and worst companion plants for peppers, quick list
My top 5 companions, one line why each helps
- Basil, repels some pests, improves flavor, and grows well in the same warm, well drained soil.
- Marigolds (French marigold, Tagetes patula), reduce nematode pressure and attract predatory insects to the bed.
- Nasturtiums, act as a sacrificial trap for aphids and whiteflies and trail over edges to save space.
- Borage, draws pollinators and beneficials, and loosens soil with deep roots.
- Onions and garlic, their sulfur compounds repel some chewing pests and they take little extra room.
The top 4 plants to avoid, one line why each harms peppers
- Tomatoes, same family and share blight and bacterial diseases, never rotate peppers in the same soil immediately after tomatoes.
- Potatoes, risk carrying late blight and other soil pathogens harmful to peppers.
- Eggplant, another Solanaceae family member that shares pests and disease pressure with peppers.
- Fennel, releases growth inhibiting compounds and attracts generalist pests that bother peppers.
What to plant with peppers, exact varieties, quantities, spacing
Herbs that pair well, with exact spacing and planting depth
- Basil, varieties: Genovese or ‘Sweet Basil’, plant transplants 6 to 8 inches apart, set 1/4 inch deeper than the pot root ball. Plant 3 to 4 basil plants per 4 by 4 foot bed around peppers.
- Oregano or Marjoram, varieties: ‘Greek Oregano’, space 12 inches apart, transplant crown at soil level. Use 2 to 3 plants per 10 square feet.
- Cilantro, sow seed 1/4 inch deep, thin to 4 inches between plants, sow in partial shade during midsummer heat spikes. Plant in small drifts at bed edges, 6 to 10 seeds per 10 square feet.
- Parsley, sow 1/4 to 1/2 inch deep, thin to 6 inches. Two to three parsley plants fit a 4 by 4 foot bed without crowding peppers.
- Garlic, plant cloves 2 inches deep and 6 inches apart in fall or in spring as green garlic; leave 6 inches from pepper stems to prevent crowding.
Flowers that attract beneficials, with planting counts per 10 square feet
- French marigold ‘Bonanza’, plant 12 to 16 per 10 square feet, spacing 8 to 10 inches, near edges and paths to limit root competition.
- Nasturtium ‘Empress of India’, plant 8 to 10 per 10 square feet, spacing 10 to 12 inches, trail along borders or containers.
- Borage, plant 3 to 4 per 10 square feet, spacing 12 to 18 inches; borage can grow 2 feet tall so give a little room.
- Calendula, plant 8 to 10 per 10 square feet, spacing 8 to 10 inches, scatter between pepper rows to attract predators.
Vegetables that share nutrient needs, with bed layout spacing
- Onions and scallions, plant in 3 rows around the pepper edge, 4 inches between scallions, 6 inches between bulbs.
- Carrots, sow 1/4 inch deep, thin to 2 inches, plant between pepper rows to use space and shallow roots.
- Bush beans, plant 3 to 4 feet away or on the north side of peppers so they do not shade them; space beans 4 to 6 inches apart.
Plants to avoid near peppers, biological reasons and practical fixes
Disease hosts and shared pests, and how to rotate or isolate them
Tomatoes, potatoes, and eggplant are in the nightshade family and share blights, bacterial spot, and pepper viruses. If you grew any of these last year do not plant peppers in that bed this season, or wait two years. If you must use the bed, solarize the soil for six weeks in summer or remove and replace the top 6 inches of soil.
Heavy feeders and allelopathic plants, and soil management if they are already present
Fennel and some brassicas can stunt peppers. If fennel grew in a bed last year, remove roots and add 2 inches of fresh compost worked into the top 6 inches, then wait one full growing season before planting peppers. For heavy feeders previously grown, apply 2 inches of compost and 1/2 cup of balanced granular fertilizer per 4 by 4 foot bed at planting, then side dress after fruit set.
Preparing soil and beds for mixed pepper plantings, exact amendments
How to check and adjust pH for peppers, with amounts of lime or sulfur per 100 square feet
Peppers prefer soil pH 6.0 to 6.8. Always do a soil test first, available from your county extension. Typical adjustment rates per 100 square feet:
- To raise pH, apply agricultural lime: sandy soil 3 pounds, loam 5 pounds, clay 8 pounds.
- To lower pH, apply elemental sulfur: sandy soil 1 pound, loam 2 pounds, clay 3 pounds.
Work amendments into the top 6 inches at least two weeks before transplanting. If you are unsure, call your extension office for exact test-based recommendations.
Compost and fertilizer quantities per square foot, and when to apply them
Mix 1 to 2 inches of finished compost into the top 6 inches of soil, about 0.08 to 0.17 cubic feet per square foot. For a 4 by 4 foot bed that equals 1.3 to 2.7 cubic feet of compost. At planting, add 1/2 cup of a balanced granular fertilizer like 5-10-10 and mix into the planting hole or bed.
Side dress with 2 tablespoons of balanced fertilizer per pepper plant every 4 weeks once blooms set. Stop feeding 3 weeks before the first expected frost to harden off fruit ripening.
Planting and arranging companions with peppers, step by step layout
Raised bed layout for a 4 by 4 foot bed with exact plant counts and spacings
- Bed size, 4 by 4 foot, depth 12 inches minimum.
- Plant four pepper transplants spaced on a square, 18 inches apart. Each plant will occupy roughly 1.5 square feet.
- Between peppers, plant carrots thinmed to 2 inches and a row of scallions 4 inches apart along the north edge.
- Plant three basil transplants, one near each of three peppers, 6 inches from the pepper stem. Plant two French marigolds along the south edge.
- Mulch with 2 to 3 inches of straw or shredded bark, keeping mulch 1 inch away from pepper stems.
If you need a visual, see raised bed gardening for beginners for bed basics and soil depth tips.
Container layout for a 15 inch pot, what to plant and what to leave out
A 15 inch pot holds one pepper plant. Use a 5 to 7 gallon container with good drainage holes. Fill with a quality potting mix and mix in 1 cup of compost. Plant one pepper transplant centered, then add one small basil plant at the edge, 6 inches from the pepper stem. Avoid planting onions or deep rooted companions in the same container. Water more often in containers; see how to grow tomatoes in containers for similar container care tips.
Midsummer care for pepper companion plantings, watering, mulch, pest patrol
Deep watering schedule, amounts per plant and soil check method
Peppers need about 1 to 1.5 inches of water per week in midsummer, more in heat waves. That equals roughly 1 to 2 gallons per pepper plant per full watering session in loose beds. Water deeply twice a week in hot weather, once a week in cooler spells.
Check soil with the finger test, push to 2 inches; soil should feel cool and slightly damp. If it is dry at 2 inches, water. For more detail on timing and morning watering, see when to water vegetable plants in summer.
Mulch depth, heat stress shading options, and scouting for common pests
Apply 2 to 3 inches of organic mulch and keep it 1 inch from the stem. For heat waves, drape 30 percent shade cloth over a simple hoop for mid day shade for 3 to 7 days. Temporary shade lowers leaf temperatures and prevents blossom drop.
Scout twice a week: look under leaves for aphids, whiteflies, and spider mites. Pick off hornworms by hand and blast aphids with a strong spray of water. If pests persist, contact your extension office for recommended control methods.
Timing by frost dates and plant stage, seeding and transplant calendar
How to tie companion seeding to your last frost date, with examples for zones 5 through 8
Peppers need soil at least 60 degrees F to set and grow. Use your local last frost date as the anchor. Here is a quick guide tied to last frost, not calendar dates:
| USDA Zone | Transplant peppers | Soil temp |
|---|---|---|
| Zone 5 | 2 to 3 weeks after last frost, when nights stay above 50 F | 60 F + |
| Zone 6 | 1 to 2 weeks after last frost, nights above 50 F | 60 F + |
| Zone 7 | At or just after last frost, when soil warms to 60 F | 60 F + |
| Zone 8 | At last frost, or plant slightly earlier if nights above 50 F | 60 F + |
Start basil indoors 6 weeks before last frost or sow outdoors after nights warm. Sow cilantro directly in drifts 3 weeks before to 4 weeks after last frost, or in partial shade in midsummer.
When to transplant peppers with companions, and staggered sowing for continuous harvest
Transplant peppers when seedlings have 4 to 6 true leaves and hardened off for a week. Plant companions like basil and marigold at the same time. Stagger cilantro and parsley sowings every 3 weeks for continuous harvest. For later summer plantings, wait until soils are cool enough for cilantro to avoid bolting.
When my pepper companion plan failed, a real garden story and the fixes I used
What went wrong, how I diagnosed it, and the exact steps I took to recover the bed
One July I crowded peppers into a raised bed and stuffed basil seedlings between stems. We had a hot week and poor drainage. The peppers went limp and some stems developed rot. I pulled half the plants and found wet, compacted soil and basil roots matting the surface.
My fixes, exact steps:
- Removed damaged plants and their roots, disposed in the trash not the compost.
- Raised the bed height by 2 inches with well drained mix, adding 1.5 cubic feet of new mix to the 4 by 4 bed.
- Worked in 1 inch of coarse sand for drainage and 2 inches of compost over the bed, mixed into top 6 inches.
- Replanted three healthy pepper transplants, spaced 18 inches, and moved basil to the south edge with 6 inch spacing. Reapplied mulch 2 inches deep, keeping it 1 inch from stems.
- Watered deeply once after planting, then followed the twice a week deep watering schedule during the next heat wave.
The lesson, plain and simple, was drainage first and do not crowd. For more on mistakes I made and how to avoid them see common mistakes new gardeners make.
FAQ heading
Can I plant basil or cilantro with peppers?
Basil is one of the best companions, plant transplants 6 to 8 inches from peppers to avoid crowding roots. Cilantro is fine if sown in drifts at the bed edge and given some afternoon shade in hot weather. Avoid burying the pepper crown with herb soil or mulch that traps moisture.
Which flowers attract beneficial insects to protect peppers?
Plant French marigolds, calendula, and borage near peppers. Marigolds draw predatory nematodes and beneficials, calendula attracts hoverflies that eat aphids, and borage brings bees and parasitic wasps. Use the counts listed earlier, scatter flowers in small clusters rather than a single big patch for best results.
