Designing a Low-Water Garden with Pebbles and Scoria

A garden built around stone rather than lawn makes obvious sense in a city that gets hot, dry summers and periodic water restrictions. Done well it is beautiful and takes almost no maintenance. Done badly it is a hot, weedy expanse of grey that nobody wants to sit in. The difference comes down to a few decisions made before any stone is ordered.

Stone is not a substitute for planting

The most common mistake is treating pebbles as the garden rather than the background to it. Stone holds heat and radiates it back, so an unplanted stone bed against a north or west wall makes the whole area hotter. Plant first — grasses, succulents, natives, anything with structure — and let the stone be the surface between them.

Choosing your stone

Tuscan 20mm Pebble is smooth and rounded in warm, earthy tones. Use it for garden beds, pathways, water features and pot plant top dressing — its Mediterranean palette is a natural partner for silver and grey drought-tolerant foliage.

Seymour 20mm Pebble is a naturally weathered river pebble in mixed tones. Use it for garden beds, dry creek beds and water features, particularly alongside native planting where you want the stone to look like it belongs there rather than like it was delivered.

7mm Scoria is the functional one. Lightweight, porous red volcanic rock, used for garden bed drainage, raised beds, potting mixes and decorative ground cover. In a low-water garden it earns its place twice: it looks deliberate, and it improves drainage and soil aeration for the plants sitting in it.

A dry creek bed

The one feature worth the effort. A shallow winding channel of Seymour Pebble, wider at the bends and narrowing on the straights, does three things at once: it gives the bed a structure to plant around, it reads as a natural feature rather than a mulch substitute, and if it follows the actual fall of your block it genuinely carries stormwater during heavy rain.

Line it with fabric, vary the width, and let planting spill over the edges in a couple of places. A perfectly even channel of stone looks like a drain, because it is one.

Weed matting is not optional

Pebbles suppress far less weed growth than mulch, because light passes between the stones. Quality geotextile fabric underneath is what makes a stone garden low-maintenance rather than a weekly chore. Cut generous crosses for plants rather than small holes, so roots and crowns are not strangled as they grow.

How much to order

Decorative pebble goes down at 30–50mm — deeper is wasted money and makes replanting harder later.

Bed area	At 40mm
5m²	0.2m³
15m²	0.6m³
40m²	1.6m³

Pebbles are the material people most often over-order. A cubic metre of stone covers far more ground than the same volume of soil appears to.

Mixing two stones

Using a pebble for the beds and scoria for a drainage zone is a good design. Just price it knowing that different materials never share a truck tray, so it is two loads and two delivery charges — which for two small quantities can cost more in delivery than in stone. Worth combining with another order if you have one coming.

Browse the Pebbles collection and the Aggregates range, or call 1300 21 21 11 to see a sample before you commit a whole bed to one colour.