Homeowners who regularly use their garden tools to maintain green spaces around their home may still be able to do more to combat climate change.
Speaking at the inaugural Royal Horticultural Society (RHS) John MacLeod Lecture, Professor Diane Pataki from the University of California, Irvine encouraged gardeners and city planners to carefully consider the balance of urban greening and environmental costs.
"In general terms we tend to feel that greening our towns and cities must be good but it is not as simple as that," she explained.
Vegetation can have a positive impact on air temperatures in cities and towns, in addition to making a favourable effect on the climate.
However, the expert warned there can also be an economic cost in addition to adverse effects on the environment that need to be given consideration.
People may wish to use garden equipment that does not necessitate the use of fertiliser on land, as greenhouse gases such as nitrous oxide can become a problem.
The ways in which gardens can mitigate flood risk and the urban-heat island effect were noted as being affected by differences in how species of plants use water, which may be something else individuals wish to take into account.
Professor Pataki said there are not enough programmes designed to measure how effective green spaces are in meeting the environmental requirements of people residing in built-up areas.
However, she acknowledged methods to monitor greenhouse gas emissions are welcome.
"We need ways to determine whether our landscape designs are effective in providing the services we intended," the expert remarked.
"Indeed there are benefits but we mustn't forget the costs such as the use of water and fertilisers."
Another activity gardeners can undertake to improve their impact on the environment is to plant more trees, as the Tree Council recently noted they can be sustainably cultivated in order to construct materials at a low energy cost.
