So far I haven't had any trouble winter sowing in 9b. I just follow the advice I've read, since I'd never heard of winter sowing until last year. I start with hardy perennials around Jan. 1st and end with half-hardy perennials and annuals through the first week of February. it seems like January is our 'winter month' for sowing. Most suggested if the temps are in the 40's, it's great for winter sowing. I do have trouble with the spring setting out in Late/Feb and March, which is all due to my inability to not sow too much.
Plus last year I wasn't sure how big my seedlings needed to be to plant out. Good thing for me they know what to do!
