The practice of growing different plants near each other for mutual benefit — pest deterrence, pollinator attraction, nutrient sharing, or physical support. Examples: basil with tomatoes, nasturtiums as pest traps.
Companion planting works by strategically pairing plants that have complementary growing needs or pest-deterring properties. In Australian gardens, this technique is particularly valuable during the warmer months (December to February) when pest pressure increases. For example, planting marigolds near vegetables helps repel aphids and whitefly, while basil grown alongside tomatoes improves their flavour and deters insects.
Different Australian climate zones benefit from various companion planting combinations. In tropical and subtropical regions (zones 10-12), consider pairing beans with corn and pumpkin in a traditional "three sisters" arrangement. In temperate zones (zones 8-9), spring (September-November) is ideal for establishing lettuce with carrots and onions. Cool climate gardeners (zones 6-7) should plant nasturtiums as trap crops to protect brassicas during autumn (March-May).
When implementing companion planting, consider your garden's microclimate and soil type. Visiting your local Bunnings will provide seeds and seedlings for popular companion combinations. Keep a garden journal noting which pairings work best in your specific location, as success varies depending on local conditions. Succession planting companion crops throughout the growing season ensures continuous pest management and soil health benefits.