Companion Plants for Onion
Discover which plants thrive alongside Onion and which ones to keep far away. Strategic companion planting boosts yields, repels pests naturally, and makes the most of your garden space.
Good Companions for Onion
Plant these near your Onion for mutual benefit
Carrot
GoodClassic companion pairing — onion scent repels carrot fly while carrot scent repels onion fly
View Carrot growing guideBeet
GoodOnions and beets grow well together; the strong scent of onions deters beet leaf miners
View Beet growing guideLettuce
GoodOnions repel aphids and other soft-bodied insects that target lettuce
View Lettuce growing guideTomato
GoodOnions deter aphids and mites; planted at the base of tomatoes they protect the root zone
View Tomato growing guidePepper
GoodOnion scent confuses and deters many insects that would otherwise attack pepper plants
View Pepper growing guidePlants to Avoid Near Onion
Keep these away from your Onion plants
Asparagus
AvoidOnions and asparagus compete and inhibit each other's growth
View Asparagus growing guideSage
AvoidSage and onions are said to inhibit each other when grown in close proximity
View Sage growing guideWhere to Grow Onion With Its Companions
Check your city's planting calendar for Onion and its best companion plants.
Frequently Asked Questions
What grows well with Onion?
Carrot: Classic companion pairing — onion scent repels carrot fly while carrot scent repels onion fly. Beet: Onions and beets grow well together; the strong scent of onions deters beet leaf miners. Lettuce: Onions repel aphids and other soft-bodied insects that target lettuce.
What should you not plant near Onion?
Pea: Onions stunt pea growth; keep all alliums away from legumes. Asparagus: Onions and asparagus compete and inhibit each other's growth. Sage: Sage and onions are said to inhibit each other when grown in close proximity.
What is companion planting for Onion?
Companion planting for Onion means strategically placing plants nearby that offer mutual benefits — such as repelling pests, attracting pollinators, or improving soil conditions. Good Onion companions include Carrot, Beet, Lettuce. Avoid planting Onion near Pea or Asparagus.