Onion deters carrot fly; carrot deters onion fly.
Allium cepa
Allium cepa grows best when paired with plants that repels pests. We've catalogued 6 beneficial companions and 2 antagonists to avoid. Every pairing below cites its mechanism — pest deterrence, nitrogen fixing, allelopathy, or shared disease.
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Onion deters carrot fly; carrot deters onion fly.
Strong aromatics like basil, garlic, and marigold mask the olfactory cues that pests use to find their target crop.
Strong aromatics like basil, garlic, and marigold mask the olfactory cues that pests use to find their target crop.
Onions help deter aphids and make efficient use of vertical space with lettuce.
Onions fit between spinach rows and help confuse aphids.
Strong aromatics like basil, garlic, and marigold mask the olfactory cues that pests use to find their target crop.
Roots or leaves release chemicals that suppress neighbouring plants. Often a one-way problem (walnut → most vegetables).
Onions and potatoes are commonly separated in traditional companion charts.
Strong aromatics like basil, garlic, and marigold mask the olfactory cues that pests use to find their target crop.
The top companions are Daucus carota, Daucus carota, Wild Cabbage. 3 more pairings are catalogued above with their mechanisms.
Avoid Pea, Potato. Reasons vary — allelopathy, shared pests, or resource competition. See the section above for each plant's specific issue.
Aromatic companions deter many pests through scent masking and alarm pheromones. Effect varies by pest species and density — most effective as part of a polyculture, not a one-plant solution.
Some mechanisms are well-documented (legume nitrogen fixation, allelopathy in walnut and fennel, nematode suppression by marigolds). Others are traditional pairings with anecdotal support. We cite both, but mark mechanism strength where available.
Un email curat pe săptămână — profile noi de plante, note sezoniere de cultivare, adăugiri în arhiva de remedii. Gratuit, fără tracking, dezabonare oricând.