Posted: 09/06/2017 at 14:36
They're 'bolting' or putting up a flower spike and will then produce flowers. You should have harvested them before they got to this stage.
You can still use them, I used the smaller leaves and thinner stems at this stage chopped up in stir fries, but they might be a little more bitter than you would like.
I would sow another lot at the end of the month ..... oriental vegetables seem less prone to premature bolting once we're past midsummer's day and the daylength hours begin to lessen.