Tradition
Bad
avoidgood
1 chart entry: 0 recommend, 1 advise against.
0 cited, 1 uncited.
Onion
Allium cepa
Amaryllidaceae
Pea
Pisum sativum
FabaceaeCan you plant onions and peas together?
Charts say no. Nobody has tested onions with peas, as far as we could find. The chart entry we found cites no source.
Why we can't give a firm answer
Garden charts advise against it. 1 garden chart entry says to keep them apart. It cites no source. Charts pass on gardening tradition; they are not tests.
List of companion plants (uncited entry) (Wikipedia)
What to plant with onions and peas
Good neighbours of both, best tested first.
CabbageWith onions: 8% more harvestWith peas: 11% more harvest
LettuceWith onions: Recommended by garden charts, not testedWith peas: 19% more harvest
CauliflowerWith onions: Bigger combined harvestWith peas: Recommended by garden charts, not tested
What to keep away from onions and peas
The evidence in detail
For readers who want to dig in: every chart entry, study and yield trial behind the answer above, with the numbers.
Tradition, research and yield trials
Research
No papers found on this pair.
Yield trial
No intercropping yield trial.
Untested folklore
Companion plants for both onions and peas
Plants that are good neighbours of each. Biggest harvest gain first; each cell links to the evidence for that pair.
| Plant | With onions | With peas |
|---|---|---|
| Cabbage | Fewer pests and draws in pest-eating insects8% more harvest from the same spaceField trial, 8 studies. Charts: recommend.Evidence for onions and cabbage | 11% more harvest from the same spaceField trial, 3 studies. Charts: not listed.Evidence for peas and cabbage |
| Lettuce | No trial foundNot tested. Charts: recommend.Evidence for onions and lettuce | 19% more harvest from the same spaceField trial, 1 study. Charts: not listed.Evidence for peas and lettuce |
| Cauliflower | Bigger combined harvestField trial, 1 study. Charts: not listed.Evidence for onions and cauliflower | No trial foundNot tested. Charts: recommend.Evidence for peas and cauliflower |
Harvest from the same space compares a bed with both crops against the same area split into single-crop beds, counting the harvest of both crops (the land equivalent ratio in yield trials).
The evidence, with sources
- Badadvises againstOnion: avoid peasList of companion plants (uncited entry) (Wikipedia)
All neighbours of onion and of pea, or every pair at once in the companion planting chart.
Have you grown onions and peas together?
Tell other gardeners what happened: spacing, pests, harvest, or ask a question. Reader notes are not checked by us and do not change the verdicts on this page.