Degree Name

Doctor of Philosophy


School of Geography and Sustainable Communities


Invasive garden plants, also referred to as garden escapes, make up the bulk of environmental and agricultural weeds in Australia and gardening remains the most significant contributor to its spread. Gardening is also regarded as the most popular recreational activity in Australia, particularly among older adults who continue to seek new and exotic plants. As a result of this, and despite the notoriety of some of these plants which are considered to be noxious, garden escapes continue to be sold in nurseries and cultivated in domestic gardens. This research is, therefore, founded upon the prevalence of invasive plants on nursery shelves and in domestic gardens from where they spread into the wider environment. It explores the links between gardening and the spread of garden escapes so as to determine how current remediation efforts might be improved upon.

Weed management strategies typically seek to provide gardeners with more information about the invasiveness of some garden plants, with the aim of fostering a change in their gardening behaviour. However, research has shown that there are factors other than an information deficit which lead to the presence of invasive species in gardens, hence the need for a shift in management outlook. Using social practice theory, this study reconceptualises gardening as a ‘practice’ that is made up of several constituting elements which work together to determine the way it is performed. These elements include the materials which aid the performance of the practice, the competences which practitioners need for a successful performance, and the meanings associated with the practice. All three have to be present in a particular configuration in order for gardening to be successfully performed and changing any one element results in a corresponding change in the practice itself. On the basis of this theoretical framework, this research explores gardening enactments to determine which elements are currently associated with it and how these relate to garden escapes. This will, in turn, highlight potential avenues through which management interventions might be better directed to ultimately foster the much needed change in enactments that lead to garden escapes.

To achieve the objectives of this study, 15 weed managers were interviewed to elicit baseline knowledge about the extent to which garden escapes are a problem within the Sydney Basin. This information was then incorporated into subsequent semi-structured interviews with 27 gardeners who were asked to give detailed accounts of their gardening enactments. The recruitment of weed managers was done mostly through snowballing from existing contacts while the gardeners were recruited through garden clubs and using radio broadcasts. All participants involved were located within the Sydney Basin Bioregion, New South Wales, which was chosen as the study site for its rich abundance of plants and nurseries as well as its eclectic diversity of gardeners.

The findings revealed that gardening is in fact shaped by underlying elements which determine its performance, and this was evident in four main ways. First, gardeners’ approach to gardening was shown to largely stem from a desire for the presence of animals in the garden space, and this led to a passive involvement in weed prevention and eradication. Secondly, experiential and social learning were shown to be the preferred way by which gardeners learn and this had to do with a perception that friends and family are the most reliable sources of gardening advice. Plant choices made by gardeners were not only driven by aesthetic ideals but also age and time constraints, which led to the cultivation of flamboyant and low maintenance plant species respectively. The fourth aspect of gardening enactments that holds some relevance for the spread of garden escapes relates to plant exchanges which the gardeners described as being a normal part of the practice. These exchanges were understood to be a physical demonstration of shared friendship ideals, and were also driven by gardeners’ need to obtain plants as cheaply as possible. So not only are plant choices determined by aesthetics and low maintenance needs but affordability was also important, especially considering that most participants are retired and on a pension. Plant swapping, however, is one obvious way by which gardeners aid the spread of potentially invasive plants from one location to another, thereby perpetuating the garden escapes problem.

Conceptually, this research advances the utility of practice theory in the area of natural resource management where it has previously not been applied. The theory offers a more comprehensive way of apprehending gardening enactments, in contrast to other research approaches which focus exclusively on either the human gardeners or non-human actors. In this way, it opens up points of management intervention that may not have been previously considered. Recommendations have been made regarding potential intervention strategies that are based on the practice approach adopted here, and these offer a more targeted way of managing garden escapes. This research also contributes to ongoing debates surrounding the suitability of interviews as a methodological tool for eliciting accounts of routine practices. The merits of this data collection instrument are evident in the detailed and uninhibited responses given by the participants of this study, in relation to such a routine practice as gardening.