Johnny's Seeds has the best growing info I've found in a catalog. Below is the brussels sprouts info. If you do a hunt for cabbage or broccoli and click on one of the varieties and then go to the bottom of the page there is link to growing info, which if I remember right will probably give you info on fall as well as spring crops.

(I have to admit to being tempted to answer "never" to the brussels sprouts question as it's about the only veggie that I'm not fond of . . . )

Here is a link that might be useful: growing brussels sprouts - Johnny's Seeds

i just direct sowed some Jade variety in a raised bed, hoping that I am not too late. Will mulch them if needed to survive hard frost but given their hardiness - able to tolerate low 20s - I am crossing my fingers for a crop!