tomato

C

Common Thyme

Thymus vulgaris

Thyme's thymol content repels spider mites, whiteflies, and other small arthropod pests of tomatoes.

C

common comfrey

Symphytum officinale

Comfrey's deep roots accumulate potassium and other minerals that improve tomato nutrient availability and disease resistance when used as mulch or companion.

M

Mexican Marigold

Tagetes erecta

Tagetes erecta roots exude alpha-terthienyl and thiophene derivatives that suppress root-knot nematodes (Meloidogyne spp.), a verified, replicated companion planting benefit for solanaceous crops including tomato.

E

eastern black walnut

Juglans nigra

Juglans nigra exudes juglone (5-hydroxy-1,4-naphthoquinone), an allelopathic compound that causes wilt and death in solanaceous plants including tomato within a 50-80 ft radius.

P

Persian walnut

Juglans regia

Persian walnut also produces juglone compounds that inhibit growth in susceptible plants though typically in lower concentrations than black walnut.

W

Wormwood

Artemisia absinthium

Wormwood produces strong allelopathic compounds including absinthin that can inhibit neighboring plant growth. Its proximity typically reduces tomato vigor.