Finding species that can tolerate heat and drought in Australian cities

Urban plantings in Australia are frequently exposed to hot and dry climate extremes. The Which Plant Where project aims to discover which plant species can tolerate future climate conditions in Australian cities. We are screening large numbers of horticultural plants, many of which are native to Australia, and ranking them according to (1) heat tolerance and (2) drought tolerance. We have found that species’ physiological tolerances do not always match their historical climatic tolerances defined using native distribution ranges (e.g. maximum temperature). The combination of heat and drought affects rankings, suggesting changing climate will pose new challenges for urban plantings.