Companion planting

Tomatoes · Basil

Classic neighbors: basil likes similar warm soil and steady water; flowers draw small beneficials when you let a few bolt late.

Tomatoes · French marigold (Tagetes patula)

Traditional companion: strong scent may mask tomato host cues for some pests; root exudates are debated—treat as a helpful row edge, not a pesticide.

Carrots · Onions or leeks

Onion scent can help mask carrot rows from carrot rust fly in backyard scales; different root depths reduce direct competition.

Broccoli / kale / cabbage · Dill

Young dill can attract beneficial wasps and hoverflies; mature dill near heading brassicas is more controversial—plan dill as an early neighbor or at row ends.

Sweet corn · Pole beans

Beans can climb corn after corn is knee-high; beans fix little N for the same-year corn crop, but roots loosen soil around the stalk.

Cucumbers · Radishes

Radishes mark rows and mature fast while cucumbers warm up; radishes can flag soil crusting issues early.

Lettuce / arugula · Tomatoes (young)

Early lettuce enjoys light shade from small tomato plants; remove or harvest lettuce before the tomato canopy closes and holds moisture on leaves overnight.

Borage · Tomatoes

Borage flowers for bees; young leaves are edible (hairy texture). Self-seeds freely—place where volunteers are welcome.

Nasturtium · Cucumber / squash

Aphids often prefer nasturtium; some growers sacrificially host aphids there. You must still scout—this is not automatic control.

Chives · Carrots

Low allium scent along a carrot row is easy to tuck in; perennial chives need a permanent edge so you do not disturb carrot roots yearly.

Peppers · Spinach

Spinach enjoys afternoon shade from pepper bushes in hot summers; pull spinach before it bolts into pepper fruiting season crowding.

Calendula · Mixed veg bed

Long-blooming calendula supports generalist pollinators; some predatory insects visit composite flowers—pair with good habitat, not sprays.

Tomatoes · Fennel

Fennel can allelopathically stress some neighbors; tomatoes near vigorous fennel often look unhappy. Keep fennel in its own corner or container.

Tomatoes · Broccoli / kale

Both are heavy feeders with big root systems; crammed together they compete for water and nutrients and reduce airflow.

Onions / garlic (active row) · Beans or peas

Folk guidance plus some field experience: very close alliums can slow legumes for unclear reasons—separate rows or time succession so peaks do not overlap.

Nightshades / cucurbits (many) · Black walnut canopy / roots

Juglone from walnut roots and litter harms many vegetables. Map walnut driplines and keep food beds outside that zone or use raised beds with barriers—research your species.