Thanks for your replies. It seems as though I will have a bumper crop in the next few weeks then. We have a produce table in our village, to collect money for Cancer Research so any spare sprouting will be bundled and sold on there.
I will take off some of the leaves to cook and see what they taste like. Should I cut the leaves off where they join the main stalk, leave a couple inches or doesn't it matter?
If I sow seeds now for next year, I could take some of the older plants out in August and eat the leaves, whether or not they have sprouted.
In the past, my sprouting was never as good as these current plants. No matter how I netted them, the butterflies always got in. This time, the new raised bed has a 6ft frame around it and the netting has been nailed on. I just have to slip the netting off the nails at any point so I can get in there to weed.