This is my first attempt at these but I love them sooo much and would be delighted to harvest my own sprouts for Christmas Day. I acquired my seeds from the lovely VP of vegplotting and they were sown in March this year. (If only I'd been so 'on the early sowing ball' with the rest of my winter greens...).
They germinated really quickly and I simply potted the seedlings on a couple of times through spring and summer. They initially stayed in the greenhouse to protect them from the pesky slugs but were moved out in late summer when we did have some hotter days.
I have two plants that survived long enough to be planted into a raised bed and since they went out, they've gone from strength to strength. They stand at almost 3 feet tall and I can see little buds growing in the leaf axils. Sprouts a gogo!