I agree with Cleo. I do not buy the expensive F1 hybrids. The old varieties are bigger and I think they taste much better. f.i. the Bedford and the roodnerf.
I have a sandy soil and dig in autumn manure in the soil, than later I stamp on it to make the soil very hard. I get a sunny spot out of the wind. Even with my poor soil I do not need supports for the sprouts. I still have two rows to go ;D
What I have to do is fight against the sea-gulls. In winter they can eat the whole garden , filled with brocoli, boerenkool, kale, sprouts, in no time, so netting is important for me.