Every gardener keeping an eye on the weather will be aware of the gradual changes to the climate that have occurred over the last few decades. There is little, if any, doubt that extreme weather events of recent years - storms, periods of drought, and floods - are a consequence of global warming, due primarily to higher levels of greenhouse gases such as carbon dioxide in the atmosphere. Climate change is a continuous process and, as plants are often sensitive to altered conditions, it is likely to present us with both challenges and opportunities. We may have to adapt both our plant choices, and our techniques, in order to maintain our gardens in the hot, dry summers and warm, wet winters that scientists predict. Adventurous gardeners may enjoy experimenting with an expanded range of plants, but lovers of tradition may struggle to maintain the perfect lawn. Gardeners should not, however, be discouraged: the oxygen released into the atmosphere as a by product of...