What Are the Best Companion Plants for Basil?
Basil grows best with parsley, chives, tomatoes, peppers and eggplant. 6 plants in our chart pair well with basil, mostly by using space and time efficiently and deterring or trapping pests; none of those pairings are research-supported.
| Plant | Why | Evidence |
|---|---|---|
| ParsleySpace & timing | Basil and parsley both want moist, fertile soil and regular cutting, so they share a pot or bed edge well. | Practical |
| ChivesSpace & timing | Chives and basil share watering needs and fit together in a kitchen herb pot. | Practical |
| TomatoesPest control | Basil is the classic tomato partner. Its scent is said to deter thrips, whiteflies and hornworm moths, but trial results are limited and mixed; the pairing works mainly because both need the same sun, heat and water. | Traditional |
| PeppersPest control | Basil and peppers need the same warm, sunny conditions; basil is said to deter thrips and aphids, though evidence is limited. | Traditional |
| EggplantPest control | Basil shares eggplant's need for heat and even watering and is said to deter thrips; the pest benefit is anecdotal. | Traditional |
| AsparagusSpace & timing | Basil fills the asparagus bed after the spear harvest and is said to deter asparagus beetles, which is unproven. | Traditional |
Good companion plants for basil, strongest evidence first.
What Should You Not Plant With Basil?
Don't plant basil near rosemary and sage. The conflicts come mainly from conflicting soil or water needs; none of the 2 are research-supported and the rest are practical or traditional rules.
| Plant | Why | Evidence |
|---|---|---|
| RosemaryConflicting needs | Basil wants moist, rich soil; rosemary wants lean, dry soil. Grow them in separate pots. | Practical |
| SageConflicting needs | Sage rots in the constantly moist soil basil needs; give each its own spot. | Practical |
Plants to keep away from basil.
Which Basil Companion Claims Are Backed by Research?
None of the 8 basil pairings in our data has direct research support: 4 rest on practical horticulture and 4 are traditional claims passed down in gardening books.
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 tomatoes, peppers, eggplant and asparagus are harmless to grow with basil, but don't rely on them for pest control — row covers, crop rotation and regular checks do more.
How Should You Plant Basil With Companions?
Plant basil about 12 inches (30 cm) apart between tomatoes or peppers, or as an edge row. Grow rosemary and sage separately in a drier spot.
Companions still need room of their own, so work out how many basil and partner plants fit in a bed with the plant spacing calculator. Planting dates for basil and its 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 basil are covered in the basil plant care guide.
Which Crops Share Companions With Basil?
Tomatoes, peppers and oregano share companion plants or growing conditions with basil, 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 parsley, chives and asparagus, and tomatoes are a good companion for basil too.
- The guide to companion plants for peppers overlaps with this one: both crops grow well with chives, and peppers are a good companion for basil too.
- The guide to companion plants for oregano overlaps with this one: both crops grow well with peppers; as members of the same plant family, the two should rotate together.
To check basil 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 basil?
- Parsley is one of the best-supported companions for basil. Basil and parsley both want moist, fertile soil and regular cutting, so they share a pot or bed edge well.
- What should you not plant with basil?
- Avoid planting basil near rosemary and sage. The most important conflict is with rosemary: Basil wants moist, rich soil; rosemary wants lean, dry soil. Grow them in separate pots.
- Can you plant basil and tomatoes together?
- Yes, basil and tomatoes are good companions. Basil is the classic tomato partner. Its scent is said to deter thrips, whiteflies and hornworm moths, but trial results are limited and mixed; the pairing works mainly because both need the same sun, heat and water.
- Does companion planting really work for basil?
- Partly. None of the 8 basil pairings in our data are backed by research, 4 are practical space or timing rules, and 4 are traditional. Flowers that feed beneficial insects and separating crops that share diseases have the strongest evidence.
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.