Philip Heinemeyer wrote:It's a great idea, but since kale is normally a biennial plant, flowering means the end of its life cycle. Producing so much seed takes a lot of energy and i doubt that it is possible for a kale plant to do that every year.
But who knows, a lot of things have been accomplished through plant breeding and maybe it could work.
Do you know purple sprouting broccoli?
I Wonder if there is a perennial form of that.
I heard about nine star broccoli but i never grew or saw it.
If you harvest the flower heads before they go to seed the plant would lose a lot less energy and might become perennial easier.
Purple sprouting broccoli can definitely go at least "short lived" perennial if you keep up with harvesting. We had some in our "sunroom garden" last 4 years because I would cut it back twice over the summer - we'd let it grow out in the fall to produce gorgeous mini broccoli heads all spring, ensuring no seed set, then cut it back to a few nodes from the base once outside leafy production was going in may...from just two or three plants that survived this treatment, we ended up with a 3x10 foot jungle of tangled broccoli stems up to 3 inches thick. The whole experiment came to an end when I worked the soil over a couple years back and tried replanting a few...they did not appreciate the disturbance and died out over that summer. We're giving it another go this year with the "rudolph" variety, which is what did the trick last time around. They wont survive our frigid winters outdoors, but did very well in our zone 7 "sunroom" greenhouse bed, producing from february through april before the heat gets to be too much and they try to run to seed.
Note: when cutting them back, be sure to leave at least 2 nodes for regrowth - you can tell these because they look sort of like a pore...look at a leaf attachment site on the main stem.
Also related is a cabbage that went rouge on us - a savoy type "des vertus". We harvested a decent head (apx 3lb) and left the stem in the ground over the winter...this is what we normally do. It survived the winter and the next spring produced two more smaller heads (apx 1lb each) as well as several "mini heads" (size of brussels sprouts) below the main heads. I brought it in this last winter and have it in a tray of soil in the sunroom, and so far it looks like it'll make another set of heads this year. None of the other cabbages behaved this way, so this one plant was just more determined to keep going I'm hoping to find out how many years it can keep this up.
It almost seems to me that any brassica can be made to go "perennial" with this sort of treatment, but the trick is finding the ones that handle that interference better than their counterparts. Sometimes it comes down to variety and sometimes it even comes down to individual plants.