Applying fertiliser, compost, or other soil amendments to the soil surface around plants rather than incorporating them. Nutrients gradually wash into the root zone with watering and rain.
Top dressing is one of the most practical and cost-effective ways to maintain soil health in Australian gardens. The process involves spreading a 2-5 cm layer of compost, aged manure, mulch, or specialised fertiliser products across the soil surface around your plants. Unlike incorporating amendments deep into the soil, top dressing works gradually as natural processes break it down, feeding your plants over several weeks or months.
In Australian gardens, top dressing is particularly valuable during spring (September-November) when plants are entering their active growth phase, and again in autumn (March-May) to prepare for cooler months. For warm climate zones (zones 9-11), top dressing helps regulate soil temperature and moisture during hot summers. In temperate zones (7-8), it provides slow-release nutrition throughout the growing season. You can source materials from Bunnings, local landscape suppliers, or make your own compost.
Top dressing works best on established garden beds, around trees and shrubs, and in vegetable patches. Apply it away from plant stems to prevent rot and pest problems. The practice is especially beneficial in clay-heavy Australian soils where it improves structure and drainage. Regular top dressing reduces the need for chemical fertilisers, making it an environmentally sustainable gardening practice. Water thoroughly after application to help nutrients begin breaking down into the soil.