One of the first things I do when I get back to England is check out the acacia that’s growing near my daughter’s house in south London. It’s 12-15ft high and is planted in the grounds of the local school – but this is first year I’ve actually been here at just the right time to actually see it flower. It’s quite a sight.

And it’s a sign of how the climate’s has changed. When I was training at Kew Gardens decades ago, the acacias were either growing in a greenhouse or trained against a sunny wall. Now, only about ten miles from Kew, this one is thriving outside and last winter - one of the coldest for a very long time – does not seem to have hurt it at all.

And it really is quite a spectacle.