The Met are not being AGW alarmists, they merely reflect the overwhelming consensus of opinion within the climatology science community. It seems that the debate on the authenticity of global warming and the role played by human activity is largely nonexistent among those who understand the nuances and scientific basis of long-term climate processes. The challenge, rather, appears to be how to effectively communicate this fact to policy makers and to a public that continues to mistakenly perceive debate among scientists. http://tigger.uic.edu/~pdoran/012009_Doran_final.pdf With specific regards to gardens and plants grown, the speculated rise in temperatures are not going to be a major problem in most cases judging by areas which have such temperature ranges now. There may be a few species which don't perform as well without their required winter chilling periods but this would be more than outnumbered by the number of 'new' species that would grow reliably, as opposed to just about surviving possibly with protection (I've grown so called exotic plants for a few years so have a little insight here). However, the biggest question as I see it is not the temperatures but the water. The temperatures will not be a problem if irrigation is available, but with drier summers coupled with our forecast population explosion means that the gardens probably won't get a look in.