I am new here and love the discussion. I have been growing brassica seeds for about ten years in the pacific northwest sometimes working with Perennial brassicas. I wanted to say wooohooo! and be encouraging, but also add a few things I know to the conversation here.
1. Western Front kale is Brassica napus. Along with all red russian types, siberian kales and rutabagas.
2. Brassica napus does not show self incompatibility and happily self pollinates most of the time. B. oleracea shows self incompatibility.
3. Brassica napus perenniality usually is the result of a stress such as coppicing, flower pinching, or tipping that pushes the plant hormones back (temporarily) into a juvenile state.
4. Selecting for third year, and beyond, vigorous growth should be a big focus, as many perennialized brassicas grow as slow as cactucs.
5. Inter-specific crosses happen, but they are very rare and often require early flower development hand pollination or bud pollination, and sometimes embryo rescue depending on species.
Here at adaptive seeds we have noticed western front kale loosing its growth tip to rot in early spring of the second year. I have a hunch that this is the trigger to its occasional regrowth a third year. However in brassicas I have learned it is never simple. One thing that always helpful is having new eyes on a difficult problem. I love hearing about these efforts. Good Luck!
