Well, this is a surprise. I've been in London and wasn't expecting to find anything moth-related. But here in the tiny window box of my son's flat is...a caterpillar. A marvellous tribute to Nature's powers of dispersal - and survival, in the way that grass pushes up through tarmac. The straggly nasturtiums are an island of greenery far (in moth terms) from the nearest park. But there are some good, big street trees, as you can see, and if you look carefully at the surrounding buildings, little sprouts of weeds are clinging on in various crevices behind drainpipes or in uncleaned gutters. Good luck to this caterpillar. Maybe I will bring you a picture of its chrysalis or cocoon in due course.
Stop press: I just had a closer inspection of the nasturtiums and there are TWO catties there. Here's the other one, having a nap on the soil. Actually they both seem to be asleep at the moment. The other one hasn't moved in the half-hour or so since I photographed it.