How Much Soil for a Garden Bed

Soil for a Standard Garden Bed

The classic garden bed along a fence or beside a house is one of the most common landscaping features in Australian homes. A typical bed of 5 metres long by 1.5 metres wide gives you 7.5 square metres of planting space. At 200mm depth, which provides adequate growing conditions for shrubs and perennials, you'll need approximately 1.5 cubic metres of garden mix soil to establish this bed properly.

One and a half cubic metres of garden mix weighs approximately 1.65 tonnes, making this a typical residential bulk delivery. This quantity sits at a good price point for most suppliers and is enough material to create a substantial garden bed from scratch. Buying this volume in bags would require roughly 75 trips with 20kg bags, making bulk delivery the only sensible option.

Choosing Garden Mix Over Topsoil

For ornamental garden beds, garden mix is generally a better choice than plain topsoil. Garden mix combines topsoil with composted organic matter, creating a growing medium that retains moisture better, drains more effectively, and contains more nutrients than topsoil alone. The added organic content also encourages beneficial soil life that helps plants establish and thrive. While garden mix costs more per cubic metre than basic topsoil, the improved plant performance usually justifies the investment.

Building Up Your Bed Level

When creating a new garden bed, you're often building up the level rather than excavating. Position your edging first, whether that's timber sleepers, steel garden edges, or natural stone. This contains the soil and creates a defined bed shape. Add soil in layers, watering lightly between each to help settle the material. Leave the final level slightly mounded, as fresh soil will compact over the first few months of watering and planting.

Planning a different bed size? Use our main soil calculator to enter your specific dimensions.