Guides · 10 January 2025 · Planted
Rain gardens and bioretention basins live or die on the planting. A plain-English guide to getting WSUD planting past council the first time.
Water Sensitive Urban Design (WSUD) is where a lot of civil jobs quietly lose time at handover. Rain gardens and bioretention basins look simple, but they’re engineered systems - and the planting is part of the engineering, not landscaping on top of it. Get it wrong and council won’t sign it off.
Here’s the plain-English version of what matters.
The planting is part of how it works
A bioretention system filters and slows stormwater through its soil media and plants. The species, density and how they’re installed all affect whether it performs. That’s why councils specify them - and why “near enough” planting fails inspection even when the basin looks finished.
Protect the surface without choking the drainage
This is the WSUD-specific trap. These systems have to drain. Dense erosion matting over a rain garden works against the asset. The right move is jute mesh - open-weave, installed first, then plant through it - so the surface is protected during establishment while water still passes through. Matting belongs on batters, not in the infiltration zone.
Plant to the spec, at the right density
WSUD plant schedules specify species and spacing for a reason. Under-planting leaves gaps that weed up and erode; the wrong species don’t tolerate the wetting-and-drying cycle. Install what’s specified, at the density specified.
Document it
Where required, planting logs, product specs and photo records make the difference between a smooth sign-off and a re-inspection. If you can show what went in and how, council has less to query.
The short version
Treat WSUD planting as engineering: mesh not matting in the infiltration zone, species and density to spec, and records to prove it. That’s a rain garden that passes the first time.
We install erosion control and WSUD planting on civil and council jobs across NSW. Got a basin or rain garden coming up? Send us the details.
