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Practice

Companion planting

Also known as: intercropping (kitchen-garden scale), polyculture planting

An agricultural practice of placing plant species together that produce mutually-beneficial interactions: nitrogen fixation supplying neighbors, taller plants shading heat-sensitive shorter ones, aromatic species deterring pests, flowers attracting pollinators that improve neighboring fruit set, and root architectures that share rather than compete for the soil profile. The Three Sisters (corn, beans, squash) is the foundational North American example. Modern garden traditions catalog hundreds of plant pairings (some empirically validated, some folk-tradition); the underlying principles — diversity over monoculture, mutualism over competition — are what cohere the practice as a real and useful gardening discipline rather than a folk superstition.

Practical

Foundational companion-planting principles, with examples:

  • Nitrogen exchange. Legumes (beans, peas, clover) fix atmospheric nitrogen via root-nodule bacteria. The fixed nitrogen leaks to neighboring non-leguminous plants through root-zone exchange and is fully released when the legume’s tissues decompose. Beans + corn (the central [[three-sisters|Three Sisters]] relationship) is the canonical case.
  • Vertical layering. Tall plants shade heat-sensitive shorter plants. Corn provides afternoon shade for [[lettuce|lettuce]] and [[spinach|spinach]] into early summer; sunflowers protect summer brassicas; squash leaves shade-mulch the ground for whatever they sprawl across.
  • Pest deterrence. Aromatic plants confuse pest-finding and oviposition by insects that locate host plants by smell. Onions and garlic deter many pests of brassicas; basil and tomato classically pair (the basil’s volatiles confuse hornworm flies); marigolds deter root-knot nematodes when planted in rotation with vegetable crops.
  • Pollinator attraction. Flowering plants in or beside vegetable beds attract bees and predatory wasps that improve fruit set and reduce pest pressure. Borage, dill, fennel, and zinnia are classic pollinator-and-beneficial-attractor companions.
  • Trap crops. Plants that pest insects prefer over the cash crop, planted nearby to draw pests away from the cash crop. [[nasturtium|Nasturtium]] for aphids (preferred over many vegetables); blue Hubbard squash for squash bugs (drawn from [[zucchini|zucchini]] and pumpkin).

Scientific

The practice’s effectiveness is mixed when evaluated rigorously. Some pairings have substantial empirical support (legume-nitrogen exchange, brassica-aromatic-companion pest reduction, pollinator-attractor floral integration); others are folk-traditional and not measurably effective in controlled studies. The honest position is that the underlying principles — diversity, vertical and temporal layering, mutualism — are robust, while specific catalog-style “X plants well with Y” pairings vary in their evidence base.

See also

Auto-generated from this entry’s typed relations: frontmatter, grouped by relation type so the editorial signal isn’t flattened.

  • Shares approach with: [[three-sisters]] · [[polyculture]] · [[permaculture]]
  • Member of: [[practice]]

What links here, and how

Inbound connections from across the wiki, grouped by lens and by relationship. These appear automatically — every entity page declares what it links to, and that data populates here on the targets.

Scientific

parallels

  • Edges and ecotones creating productive edges within a single planted bed — same principle at the bed scale

Practical

combines with

  • Borage tomato-and-strawberry companion (pollinator support, mineral mining); allows multi-species pollinator-strip composition
  • Comfrey the canonical food-forest understory companion; chop-and-drop around fruit trees
  • Marigold (Tagetes) interplant in tomato, pepper, eggplant, and cucurbit beds for nematode suppression
  • Nasturtium the canonical aphid trap crop in mixed vegetable beds; pairs especially with cucurbits, brassicas, beans

shares approach with

  • Guild Design guild design is companion planting extended to multi-species, multi-function permanent groupings around a central anchor plant
  • Integrated pest management companion planting is one of the cultural-control methods within IPM

combines

parallels

  • The hand as tool garden intuition — what to plant where, when, with what — is largely hand-and-eye knowledge built over years of attending to one specific piece of ground

9 inbound links · 4 outbound