Greener walls for a more resilient landscape

As sustainability becomes a defining priority in landscape design, infrastructure and land development, retaining wall systems are being asked to do more than simply hold ground. They must reduce environmental impact, support living systems, blend into sensitive sites and still deliver engineered performance. Flex MSE® meets that brief by combining the strength of mechanically stabilised earth with the visual and ecological benefits of vegetation.

Flex MSE is a patented vegetated wall system built from geotextile bags and interlocking plates. Once filled and installed, the bags act as both structural units and planter blocks, creating a retaining wall or erosion control structure that allows the planting of grasses, ground covers, flowers, vines and small shrubs into the face of the wall. The result is a living structure that softens hard edges and integrates with surrounding landscapes, rather than imposing a concrete or steel finish on the site.

The environmental advantages are significant. Traditional retaining walls often rely on concrete, steel, rebar, wire mesh or formwork, all of which carry high embodied carbon and can create visually harsh outcomes. Flex MSE provides structural performance without the need for these conventional materials in the wall face. With a 120-year ASTM design life, while producing 97% lower greenhouse gas emissions than conventional concrete systems and 98.5% less than steel, the Flex MSE system also includes recycled content and recyclable components.

“Flex MSE is the only geosynthetic system in the world with an EPD/LCA,” says Matthew Strachan, Flex MSE consultant for New Zealand. “It gives designers, engineers and clients clearer evidence of its lifecycle environmental performance.”

That Environmental Product Declaration is especially relevant for projects where sustainability claims must be backed by measurable data. As councils, developers and landscape architects work to reduce embodied carbon, an EPD helps support more transparent material selection. It allows Flex MSE to be considered not just as an aesthetic alternative to hard retaining structures, but as a lower-impact engineered solution.

Flex MSE is particularly well suited to eco-sensitive locations. Its ability to vegetate over 100% of the wall face makes it appropriate for waterways, stream banks, river protection, coastal areas, culverts, detention ponds and other places where land meets water. The system is water and root permeable, and the bags provide filtering functionality that helps prevent soil particle seepage, while still allowing biological growth.

Aesthetically, the transformation is one of Flex MSE’s strongest benefits. A conventional retaining wall often remains a hard, exposed surface. A Flex MSE wall can become part of the landscape. Hydroseeding, live planting and live staking can all be used, with suitable vegetation including grasses, ground covers, perennials, vines and small shrubs. Over time, the wall becomes greener, softer and more visually connected to its setting.

For New Zealand landscapes, where infrastructure frequently intersects with coastlines, waterways, slopes and residential amenity areas, Flex MSE offers a practical balance: engineered strength, lower embodied carbon, verified sustainability credentials and the natural beauty of a living wall.

For more on Flex MSE and pictured project visit: www.advancelandscape.co.nz/flex-mse