Giant Miscanthus is adapted to a broad growing range. Europe has shown successful stands from southern Italy (37° N latitude) to Denmark (56° N latitude). In the U.S. it has been successful from the Gulf of Mexico to central Canada. Temperate and tropical climates with good annual rainfall are the most favourable conditions for cultivating Miscanthus. Miscanthus does not grow at low temperatures below a threshold of 6 degrees C.
Annual rainfall and soil water retention will strongly influence the yield of Miscanthus at any site. Miscanthus possesses good water use efficiency when considered on the basis of the amount of water required per unit of biomass and Miscanthus roots can penetrate and extract water to a depth of around 2m. However, to achieve high yields the crop may need more water than the crops that it may replace. Irrigation is not justified by the value of increased biomass obtained. In times of severe drought, the foliage of Miscanthus will first show leaf rolling and then die back from the leaf tip. This will reduce yield however the crop will survive and re-grow the following year.