Preference for and performance of some Australian native plants grown as hedges

Indigenous and other native plants are commonly restricted to informal or naturalistic designed landscapes. This research project investigates the use of native plants as a formal landscape element – the hedge. A multidisciplinary approach was used with distinct horticultural and social science components. The first study explored the response of 14 native and one exotic species to hedging every 4 months. Digital imaging techniques were used to measure changes in growth, density and canopy distribution. All species responded well to hedging, greatly increasing in density. Significant differences in growth rates and shoot regrowth patterns were recorded between the species. Some hedges grown from genetically diverse plant material had noticeable morphological variations and would be more suited to use as informal hedges, however growth rates were found to be a much better predictor of hedging performance than genetic uniformity. A second study explored gardeners’ (n=162) preference for these native hedges. Photomontages were created of the hedges grown in the horticultural experiment and a photo-questionnaire distributed to several groups of gardeners. The preference results showed that many gardeners did like some Australian plants used as hedges. Significant differences in preference were found between species. A principal components analysis found that factors positively affecting preference for hedges included neatness, foliage colour (green and grey), presence of flowers and the absence of visible woody stems. In general, genetically diverse hedges were slightly less preferred than genetically uniform hedges, but some genetically diverse hedges were highly preferred. Personal style preferences based on gardeners’ expressed gardening behaviour were also observed, with grey and softer hedges preferred by those participants with low-maintenance, drought tolerant or native gardens.