Learning from failure: evaluating plant performance in urban landscapes

Plants in urban landscapes are generally the result of design process that encompasses some level of plant selection. Typically this includes plants selected to meet specific outcomes, based around the overall design objectives for a project. However, while the landscape design process is generally well described in the literature, plant selection is not. There are few examples of analytical approaches to link specific criteria against plant choice and fewer studies evaluating plant performance in the landscape over time, particularly against original design use. This provides challenges to improving future design development and plant selection decision-making. We discuss two cases studies of landscapes in urban Melbourne where there were significant rates of plant failure. The results showed that failure can be attributed to multiple factors around site issues, plant biological tolerances and maintenance, but is also related to poor plant selection. We contend that to improve plant performance in urban landscapes we need to learn more from plant failure to improve decision-making. This relies on increasing discussion around plants in the landscape, building greater opportunities for professional development for landscape architects and building trans-disciplinary approaches to design, particularly linking designers to plant users.