Thin broccoli & other veg

*I planted winter veg last year - purple spouting broc., cauli, savoy cabbage and kale. The purple broccoli has only very thin stems with a few weedy 'heads' - barely big enough to eat - on the ends and the stems are now beginning to flower. Have I missed it? Is it safe to eat if there are flowers on the stems as well as the purple bits?
*Also there is no sign of caulis, and the cabbage plants are quite tall with lots of great leaves but no real heads - yet. Is it still a bit early for these or have they failed?

 

Doesn't sound good :-(
If the PSB has gone to flower then I'm afraid that's pretty much it. I've just pulled mine up after it had been in flower for a couple of weeks (the bees seemed to like it - I didn't) but I have been eating it since february...