Tyfon / Holland Greens

This is a hybrid of a stubble turnip and Chinese cabbage that sounds amazing.
Self sowing, mild, cold hardy?,heat resistant abbut it seems to have disappeared from American seed suppliers.
Yet it's still available from some UK suppliers.

Komatsuna seems pretty close, but it bolts pretty easily.

I brought some seeds here a few years ago and tried it a few times-- never with any success. The slugs got most of it, and what did survive didn't get huge and had that miserable look that made me think we're too warm (9b, although i can grow artichokes and kale just fine). I bet it would do better in colder places, and if you've got slugs/snails I would start it in containers or whatever and only transplant out once they're strong enough to stand up to a slug or two.

(I bought it because it was advertised as loving heavy clay, which is very much what I have)

I grew some one year. The taste was so strong even my chickens refused to eat it.

Seems like they are not the amazing plant that is advertised!
Just as well, seems like they are hard to obtain anymore.