How Do I Use Companion Planting in a Small Garden?

Small gardens arguably benefit more from companion planting than large ones — when every square metre counts, making each plant do more than one job is genuinely valuable. In a limited space, companion planting helps pack in more crops, reduces the need for separate pest control measures, maximises the use of vertical growing space, and keeps the soil productive. The principles are the same as in a large garden, but the application needs to be more deliberate and space-efficient.

Interplanting and succession

Interplanting means growing different crops in the same space at the same time — typically a fast-maturing crop among a slow one. Lettuce or radishes between tomato plants uses the ground while the tomatoes are still small. Spring onions or basil at the foot of climbing beans fills the space below the canopy. As the fast crop is harvested, the slower crop fills the space. Succession planting (sowing a new crop every two to three weeks) combined with interplanting means the bed is never bare and is always working.

Vertical layering

In a small space, growing vertically is essential — and companion planting can make use of every layer. Climbing beans or cucumbers growing up a trellis on the south-facing side of the plot provide a productive vertical element. Low-growing companions — thyme, compact marigolds, lettuce — fill the ground layer below. Medium-height crops occupy the space between. Using walls, fences, and frames as growing surfaces rather than just plot boundaries dramatically increases the productive area.

Choosing multi-function companions

In a small garden, every plant needs to justify its space. Choose companion plants that serve multiple roles: nasturtiums that act as trap crops for aphids and are also edible; chives that deter aphids and are a culinary herb; borage that attracts pollinators and whose flowers are edible; white clover that fixes nitrogen, suppresses weeds, and feeds bees. Avoid large, spreading companions like tall fennel or giant sunflowers that would take up significant space for limited benefit in a small plot.