What Are the Best Companion Plants for Cauliflower?
Cauliflower grows best with dill, sweet alyssum, spinach, lettuce and nasturtiums. 9 plants in our chart pair well with cauliflower, mostly by deterring or trapping pests and using space and time efficiently; 2 of those pairings are research-supported.
| Plant | Why | Evidence |
|---|---|---|
| DillPollinators & beneficials | Flowering dill feeds the parasitic wasps and hoverflies that attack cabbage worms and aphids on cauliflower. | Research-supported |
| Sweet AlyssumPest control | Sweet alyssum's tiny flowers feed hoverflies and parasitic wasps; hoverfly larvae eat the aphids that attack cauliflower. | Research-supported |
| SpinachSpace & timing | Spinach uses the open space between young cauliflower plants without competing much for water. | Practical |
| LettuceSpace & timing | Lettuce grows in the gaps between young cauliflower plants without competing much for water. | Practical |
| NasturtiumsPest control | Nasturtiums often draw aphids and cabbage white butterflies away from cauliflower as a sacrificial trap crop; results vary, and infested nasturtiums must be pulled. | Traditional |
| CeleryPest control | Celery's scent is a traditional deterrent for cabbage white butterflies on cauliflower; both need rich, moist soil. | Traditional |
| OnionsPest control | Onion-family scent is said to mask cauliflower from cabbage moths and aphids; trials show small effects at best, but the narrow, upright plants take little space. | Traditional |
| ThymePest control | Thyme scent is said to confuse cabbage moths looking for cauliflower to lay eggs on; some trials found fewer eggs, others no difference. | Traditional |
| BeansSoil & nutrients | Beans grown before cauliflower leave nitrogen-rich roots and leaves in the soil; side by side, the benefit this season is small. | Traditional |
Good companion plants for cauliflower, strongest evidence first.
What Should You Not Plant With Cauliflower?
Don't plant cauliflower near tomatoes. The conflicts come mainly from competition for space, light or water; none of the 1 are research-supported and the rest are practical or traditional rules.
| Plant | Why | Evidence |
|---|---|---|
| TomatoesCompetition | Both are heavy feeders that compete for nitrogen. The old rule to keep tomatoes and cabbage-family crops apart rests on competition, not proven harm — some growers even report fewer diamondback moths near tomatoes. | Traditional |
Plants to keep away from cauliflower.
Which Cauliflower Companion Claims Are Backed by Research?
2 of the 10 cauliflower pairings in our data are research-supported: dill and sweet alyssum. Of the rest, 2 rest on practical horticulture and 6 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 nasturtiums, celery, onions and thyme are harmless to grow with cauliflower, but don't rely on them for pest control — row covers, crop rotation and regular checks do more.
How Should You Plant Cauliflower With Companions?
Space cauliflower 18 to 24 inches (45–60 cm) apart with lettuce or spinach in the gaps; keep the soil consistently moist and plant dill or sweet alyssum at the bed ends.
Companions still need room of their own, so work out how many cauliflower and partner plants fit in a bed with the plant spacing calculator. Planting dates for cauliflower and its companions follow your local spring and fall frost dates, so cool-season partners can be sown together in early spring or late summer for a fall crop.
Which Crops Share Companions With Cauliflower?
Broccoli, cabbage and kale share companion plants or growing conditions with cauliflower, so their companion guides help plan the same bed or rotation.
- The guide to companion plants for broccoli overlaps with this one: both crops grow well with dill, sweet alyssum and spinach; as members of the same plant family, the two should rotate together.
- The guide to companion plants for cabbage overlaps with this one: both crops grow well with dill, sweet alyssum and nasturtiums; as members of the same plant family, the two should rotate together.
- The guide to companion plants for kale overlaps with this one: both crops grow well with dill, sweet alyssum and nasturtiums; as members of the same plant family, the two should rotate together.
To check cauliflower 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 cauliflower?
- Dill is one of the best-supported companions for cauliflower. Flowering dill feeds the parasitic wasps and hoverflies that attack cabbage worms and aphids on cauliflower.
- What should you not plant with cauliflower?
- Avoid planting cauliflower near tomatoes. The most important conflict is with tomatoes: Both are heavy feeders that compete for nitrogen. The old rule to keep tomatoes and cabbage-family crops apart rests on competition, not proven harm — some growers even report fewer diamondback moths near tomatoes.
- Can you plant cauliflower and broccoli together?
- Yes, cauliflower and broccoli can share a bed; neither is known to help or harm the other. Both belong to the cabbage family (Brassicaceae), so they share pests and diseases — rotate them together and don't follow one with the other.
- Does companion planting really work for cauliflower?
- Partly. 2 of the 10 cauliflower pairings in our data are backed by research, 2 are practical space or timing rules, and 6 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.