Well sometimes things get mixed up. A six pack of veggies can get misplaced by a customer who decides they want something else- and wind or misadventure can misplace a tag.
Then you end up with something like this.
It’s… a brassica!
Probably Brassica oleracea judging by the shape of it.
But it’s a little strange…
Purple stems and green leaves…
The stems don’t seem to be swollen so probably not a kohlrabi…
Could be a collard or a kale?
Growth comes from the inside… but that’s common for almost all brassicas.
Brussels? Cauliflower? Broccoli? A straight up cabbage?
Well. I suppose I’ll just have to grow it and find out!
The leaves aren’t too damaged from the ubiquitous cabbage moth- I did give it a spray down with B.t. regardless.
Anyways…
🎶mystery plant, it’s a mystery plant🎶
🎶gonna put it in the ground and see what comes up🎶
Of course the space requirements of a Brussels versus a cabbage are very different so…
Stay tuned.
The Neanderthal Gardens 
I believe that they are purple cauliflower.