Companion planting

Companion planting means placing certain plants near each other because of a beneficial relationship, such as one plant repelling pests that trouble another, one attracting pollinators that both benefit from, or two plants simply using space and light efficiently when grown side by side. On a balcony, where every container counts, combining plants this way helps make the most of limited room.

Common balcony examples include planting basil near tomatoes, where the strong scent is thought to discourage some pests while the two share similar sun and water needs, or tucking marigolds among vegetables to draw in pollinators and predatory insects that help control aphids. Herbs and shallow-rooted greens are also often planted around the base of a taller container plant to use the same pot space more fully.

When planning companion combinations, matching sun, water and soil needs matters more than the specific pairing, since two plants with very different watering requirements will struggle in the same container regardless of any pest-repelling benefit. A common mistake is crowding too many companion plants into one pot for the sake of the pairing, which increases competition for root space and can reduce the harvest from all of them.