Both ... start inside and transplant outside as soon as possible.

And then in late summer (8-10 weeks before your first expected frost) plant the seeds or transplant some for a fall/winter harvest.

You can grow brassicas in either spring or fall. Check seed catalog listings, as some varieties are better In fall. I'm in 6b as well and i wouldn't attempt cauliflower or brussels sprouts in spring. I do grow broccoli and cabbage in spring - this year i'm growing Belstar broccoli and Farao and Copenhagen cabbage. I'm an organic grower, but if you aren't concerned about organic seeds, there are a number of other varieties you can try. You'll probably have better luck with hybrids, they are better able to withstand the heat you'll be dealing with at harvest time. I have seen at least one type of cauliflower that was listed for spring production, but i haven't tried it yet myself.

Thanks very much for the insight! I think I'll stick with late summer. Plenty to grow this spring anyway. Thanks again.

And just for future reference, in spring you can normally start brassicas indoors about 4 weeks (3 weeks would be better) ahead of when you plan to plant outside. It's not good to have rootbound, overly mature, and/or otherwise stressed brassicas.

Rodney

Concur: the greatest problem with broccoli and cauliflower is buttoning (coin size heads from stressed plants) Harrden the plants off and they stand light freezes down to about 22 degrees. For spring planting, sow heads indoors about 6 weeks before transplanting time, which should be about two weeks before your average frost date. Fall planting is a bit more tricky as cauliflower and to a less extent broccoli are susceptible to freezes when heading. You have to look at the DTM and back up your seed starting to get a harvest.

That said there are many cauliflower varieties with short DTM that do well in spring planting. Montana, Rushmore, Majestic come to mind.

Here is a link that might be useful: Brassicas

I sow and raise the plants for quick germination, fast growing, hardening them off from the get-go, and setting them out in 26 days from sowing.
For fall I start cauliflower on June 22 and keep them outdoors on the picnic table the whole time unless a storm hits or perhaps some shade if extra hot for the afternoon. Water extra well after setting out.

My (limited) experience is that I winter sow brassica seeds in January. They will sprout when mother nature nudges them to. Last year I planted in raised beds 3 weeks prior to average last frost. They (cabbage, broccoli, and cauliflower) all did well. I sowed seeds for the fall crop ~ the 7th of July. I had nice fall crops of cauliflower and broccoli, but the cabbage didn't have enough time to form. I may sow seeds this year 1.5 - 3 weeks earlier for cabbage and probably 1 week sooner for the other 2.

For you, you will want to know your average last freeze (spring) and average first freeze (fall) and sow & plant accordingly.

Also see link below to winter sowing.

regards,
tom

Here is a link that might be useful: wintersowing FAQ

The planting dates are really confusing and hard to believe. As others have said, cabbage and broccoli can be double-cropped in 6B, with spring crops seeded indoors in late Feb, and fall crops seeded in early July. Cauliflower seeds need to be started in early July, too.

I have never gotten decent B sprouts or cauliflower from spring plantings. I now start B sprout seeds the first week of June; the plants bear in November.