Sydney Metro planting trials: sowing the seeds for urban biodiversity

By Jon Hazelwood, Hassell Principal

Biodiversity loss is a pressing issue in contemporary cities. Our Sydney Metro planting trials aim to achieve a beautiful, biodiverse ground-level landscape that will inform the design of future public landscapes across the city.

Eight thousand plants and 110 species. Designed in collaboration with Sydney Metro, John Rayner and Clare Farrell at the University of Melbourne, our Sydney Metro planting trials in Australia have, at the time of writing, been in the ground for four weeks.

By closely monitoring the progress of the planting, we can determine the most successful plants and plant mixes over time, as well as assess growing medium and biodiversity benefits.

Protecting and adding to biodiversity should be an essential priority in urban environments, especially in areas with little natural habitat.

The positive physical and mental health benefits of access to beautiful, bio-diverse, floral landscapes are well-documented. Studies have shown that the most significant biodiversity occurs in the ground and shrub layers of vegetation, as opposed to either lawns or the tree canopy above.

The planting trials are located at the Hills Showground Metro Station in Sydney and replace existing ground-level planting with a wide range of colourful flowering plants. The new planting is naturalistic in style and uses a variety of predominantly native species.

Low-maintenance landscapes typically include a small range of robust plants with limited visual appeal and low biodiversity value. To improve the quality of low-input public landscapes and make our cities more attractive and biodiverse, these plantings have been designed as a novel, low-cost and resilient alternative to conventional public plantings.

The mixes are diverse shrub and herbaceous plants that can be maintained by coppicing (occasional hard pruning to 10-20cm high) to promote repeat flowering and vegetation density, which helps exclude weeds.

These planting trials are the result of a design collaboration between Hassell, Sydney Metro and our friends at the University of Melbourne’s Burnley Campus.