growing winter cauliflowers

we usually start sowing some of our winter cauliflowers seed in October last year we grew a variety called Boris that produced very good size cauliflowers

so last year I set the seed in trays then pricked the plants out into pots and left in the greenhouse till spring then after winter we  planting the cauli plants out in the allotment in spring but because it took some space in the greenhouse it held us up for other spring sowings so this year I'm going to prick out the plants into a covered raised bed to see how they produce but I'm not sure if  I should plant them into pots and place the pots in cold  frame till spring then plant them out in pots in netted raised bed come spring