Sorry to miss Romanesco Cherry, only grew it recently.
Space at 21in/52cm, like a cauliflower.
Sow 5th-7th June for October harvests and 10th-12th for November harvests, approx.
Kaibroc also is new to me so not in the books, yet. Sow 12th to 25th July, around 20th is a good average for harvests Oct-Nov.
Yes sow trays & prick out deep is good.
