I have grown Durham Early variety over winter for the last few seasons, I always wait for them to form hearts before harvesting, but I recently read that true spring cabbage are just the leaves. They do eventually form hearts but have I been waiting too long then? Do any early varieties form hearts in the spring at all? Thanks for any info, I have looked on line, but there are many different answers to the same question, hence the confusion.....well, for me anyway !