Drought

The recent dry summers in the U.K. have caused problems to many established native trees causing stress and premature leaf fall or even death. The hardy Eucalypts grow naturally in areas that have either an even distribution on rainfall or a winter maximum. They usually receive a minimum rainfall of 800mm (31 inches) per year but are able to tolerate lower rates. Like all trees they initially need sufficient moisture to establish. However, once established, they seem to be well able to withstand the sort of droughts recently experienced in the U.K.

This may because of the hanging nature of the adult leaves of most of the Eucalypts which can reduce transpiration loss by avoiding some overhead solar or sky radiation. Whereas conifers or broad leaf trees, because of their leaf arrangement, will shed leaves as a response to drought.