It sounds as if you bought cabbages which have already bolted....They should look like nice rounded rosettes...cabbages/ornamental cabbages/kale will bolt if they were grown in TOO warm of temperatures (above 50)...OR if growing temps were not cool enough, but not warm enough to bolt, the plants may have just become leggy. Planting is best down after the first frost...color also intensifies with each frost.

Try a google search on Ornamental cabbages or kale for more info...I'm not always too clear :)

Vera

And a word of warning: slugs, snails, and pretty much all buggers in general will eat them up and lick their chops...prepare for that in whichever way you feel most comfortable. Sand, rough gravel, and crushed eggshells are good organic/ non toxic methods (slugs/snails don't like scraping up their bodies trying to crawl over them) and I've heard there are copper tape barriers which work also.
Amanda 'romando'