We let our kale go to seed this spring. Usually in Wisconsin it doesn't make it through the winter but it did make it with the cover frame (cold frame).
It finally started to yellow, so we cut it and put it in bags to dry. I rustle it everyday to keep it non-compacted. I should have enough seeds for kale for the next 5 years or more.
For the most part I am done starting seeds, though I just started some more dill, some mullein for medicinal purposes, some roots of green onion to get more green onion, and some thyme (because we never have enough).