We had our lunch outside this weekend, sitting comfortably on the patio . And it was unusually peaceful except for some crackling and popping sounds in the border. We assumed it was the blackbird scrabbling around - not that I've seen any birds in the garden for weeks. But the noise carried on, so I got up to investigate.

Ker-pow! Another pop and something flew towards me. Eh? A blackbird hurling soil at us? Ker-ping! Another pop and another missile. Then a whole series of popping and ker-pinging.

Eventually I saw what it was. A small round black seed from a Euphorbia mellifera bush. So we picked some of the seedcases and put them in a bowl with a clear plastic lid over it. And, as the temperature rose, they all exploded like popcorn.

They did the same today, but only when the temperature rose to a certain level.

Never known it before. Climate change, anyone?