This was the first failure and it was really caused by trying to be too clever.
The original plant was quite big as it was the only Aster the shop had and it was a plant I wanted to try out. After reading a bit online it suggested that you could split the plant so that’s what I did. One half was immediately planted into Maggie and as you might see from the original pic, it was flowering well. Sadly this didn’t last and due to my inability to water properly (more some other time on this!) and the ham-fisted attempt at splitting the plant, it quickly started to lose flowers and stop growing.It had also developed a bit of mould which sadly appears to be something that I’ve managed to attract on other plants too.