Whether it was due to the weather (August was awful), or whether I used two different types of compost, I don't know, but they fared very differently. The first lot was initially nibbled by a caterpillar when they were still small, which nearly wiped them out, but fortunately they recovered though they then developed very slowly, producing some very dense, strong-flavoured radishes that were only just edible. The other lot, sowed a week later were completely different and very much better. Here is photo of the two pots side by side:
Since Jane is going away this week to spend a few days with our daughter in France, I wanted to harvest the radishes before she disappeared, even though they are mostly still on the small side. Here you see the evidence that I did indeed grow them in a pot:
There were only about a dozen that were worth picking, but in my eyes that is nonetheless a significant victory!
See, there are a couple of very nice ones in that bunch. They are "Cherry Belle", by the way.
I don't think this is going to persuade me to regularly grow radishes in pots, but at least it proves that it can be done.