Ally

It's always nice to see these annuals appear on the green roof. Just because they were there last year, and just because I spent time shaking out as many seed pods as I could find, it doesn't guarantee they will come back - tgey are notoriously fickle about germination and establishing a population

Having a green roof that we can only see either the edges of from ground level, or more of by getting out a ladder, extending and climbing it is a bit silly really, but it does make a nice surprise when you finally get around to it. It also makes low-level shots of the plants a bit easier. I tried to make pictures with some sweet, red common vetch and this in the same frame, but this solo shot, with the flowers showing how they change colour as they age, came out better

Of course it is Yellow Rattle. It is the darling of wildflower gardeners, because it produces specialised roots that can penetrate the roots of grasses and steal their nutrients. This weakens the grass and helps prevent it overwhelming the wildflower plants. The pretty green and red capsules behind each flower (worth zooming on) are the seed pods; these dry out and the loose seeds within rattle against the dry husk of the pod in the wind - inspiring its name

I saw plantain, ox-eye daisy, some species of yellow vetch, as well as kidney vetch, red and white clover, knapweed not quite in flower and a mass of tall meadow buttercups. It has been a bumper year for buttercups everywhere, I think