Onion

Onion

Allium cepa
Amaryllidaceae
Potato

Potato

Solanum tuberosum
Solanaceae

Can you plant onions and potatoes together?

It depends. The sources disagree about onions and potatoes. Results on pests were mixed in a field trial, while onions kept pests off potatoes in a field trial.

Why it depends

What to plant with onions and potatoes

Good neighbours of both, best tested first.

How each one was tested, with the evidence

What to keep away from onions and potatoes

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

Tradition

Good

1 chart entry: 1 recommend, 0 advise against.

All entries cite a source.

Research

Mixed

2 papers found: 1 positive, 0 negative, 1 mixed.

pest suppression x2

auto-classified not reviewed by a person

Yield trial

No intercropping yield trial.

It's complicated

What happens above and below ground

Each animation illustrates a mechanism a study reported for this pair. Pick a card to focus on it.

ABOVE GROUNDBELOW GROUNDsubsoilOnionAmaryllidaceaePotatoSolanaceaeABOVE GROUNDBELOW GROUNDsubsoilOnionAmaryllidaceaePotatoSolanaceae
Everything at once.

Companion plants for both onions and potatoes

Plants that are good neighbours of each. Biggest harvest gain first; each cell links to the evidence for that pair.

PlantWith onionsWith potatoes
BroccoliNo trial foundNot tested. Charts: recommend.Evidence for onions and broccoliBigger combined harvestField trial, 2 studies. Charts: not listed.Evidence for potatoes and broccoli

The evidence, with sources

ResearchMixed2 entries
TraditionGood1 entry
Plan a bed with onions and potatoes

All neighbours of onion and of potato, or every pair at once in the companion planting chart.

Have you grown onions and potatoes 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.