This morning, a number of the Astrophytums were showing swollen buds and were clearly ready to flower. It didn't take long, once the sun hit them, for the flowers to start coming: first the Astrophytum myriostigma nudum showed the same flower that had so carefully taken a look yesterday, then the Astrophytum ornatum (two of them) and finally the Astrophytum myriostigma.
The A. myriostigma was very special. It showed nine flower buds. This is how it looked at twenty-past-eleven, shortly after the sun had reached around the shade:
By an hour and a half later, at ten to one, the buds had swollen considerably and were showing signs of opening:
And this photo was taken at five minutes to two, by which all nine flowers were being proudly displayed in the glorious sunshine.
The opening of the buds is a fascinating process to follow: sit and watch and it is as if nothing happens, but dare to go away for a few minutes and, when you return, the change is obvious. Perhaps even more fascinating is that, when the sun passes behind the house and the shade falls again on the cacti, the flowers close up into their neat little packages. Here's that same A. myriostigma at almost five-thirty. There is still plenty of light, of course, but the plant has been in the shade for half an hour or so, and its flowers have somehow packed themselves away, ready for tomorrow's display.
You can see more flowers from this year's cacti in my Cactus flowers 2012 album, which will be updated as the flowers come along. (And there are plenty of other albums there for you to enjoy, too.)