[Seedgeeks] what makes a perennial?

[dan at openaccess.org]

What would we have to do to have perennial collards or kale?

This is not well known, in my opinion.  However, there must be several
genes that work together to suppress annualism.

There are widely scattered "pockets" of brassicas that are perennial.  The
only one I know of in the US that is grown by cuttings is the TREE
COLLARDS that is sometimes offered by Ecology Action/Bountiful
Gardens/John Jeavons. He says that one is not cold hardy and as I recall
does not flower much. The lack of cold hardiness is why I have not pursued
getting it.

http://www.actahort.org/books/407/407_5.htm

Looks like we need to collect some plants via the rare seed and go from
there.  Unless we find a way to force the TREE COLLARDS to flower and
cross that. More diversity would be better though.

Dan