A Comparison of Purchasing Behavior and Recognition of Invasive Plants by Gardening Consumers and Master Gardeners in New Jersey

The sale of horticultural plants has played a significant role in the introduction and spread of invasive plants in North America.  The purchase of invasive plants by home gardeners can have serious long-term effects on the ecology of wooded areas and open space.  A survey was conducted of New Jersey residents in 2008 and 2009 to assess their perception of invasive plants and to document their purchasing behavior.  Eight hundred and seventy-four consumers particpated in the survey; 421 randomly selected gardening consumers and 453 Rutgers Master Gardeners.  Each participant was shown labeled photos of twelve plants and was asked whether they believed the plant was invasive, non-invasive or they were unsure.  The survey participants were offered a definition of invasive based on the 2004 New Jersey Executive Order.  The participants were also surveyed to rate factors that influence their purchase of landscape plants, which included price, quality, pest resistance, deer resistance, plant origin and invasiveness.  Both groups, consumers and Master Gardeners, rated English ivy (Hedera helix) the highest percentage for invasiveness; 81% and 83%, respectively.  Similarly, 52% of the respondents from each group rated porcelain berry (Ampelopsis brevipedunculata) as being invasive.  Master Gardener participants showed a greater response for the invasive potential of nine of the twelve featured species compared to the general public.  Seventy-one percent of the Master Gardeners regarded Japanese barberry (Berberis thunbergii) as invasive compared to 60% of the consumers surveyed.  Master Gardeners also rated high invasive potentials for Norway maple (Acer platanoides) 67%, burning bush (Euonymus alatus) 59% and butterfly bush (Buddleia davidii) 63% compared to the consumer group's response of 39%, 31% and 35% respectively.  Survey results regarding purchasing behavior were similar for both groups with 79% of the surveyed consumers selecting non-invasive plants while 84% of the Master Gardeners chose non-invasives.  Twelve percent of the Master Gardener respondents spent five hundred dollars or more annually on landscape plants while 17% of the consumers spent this amount.  The findings from this survey showed that while both groups sought to make responsible plant purchases with regard to disease, insect and deer resistance, water conservation and maintenance requirements; trained Rutgers Master Gardeners showed overall higher recognition of invasive species that are problematic in New Jersey.  They also reflect that consumers feel they are choosing non-invasive plants when in fact they cannot readily identify plants with invasive qualities.