When I picked up the plants, the lady wasn't there. She'd just left them trustingly on her porch and I picked them off, dropping off the alpines and some cash too.
It wasn't until I got to the car that I notices the artichoke looked very much like a Shasta daisy. After some serious texting, I met her back at her place to make sure it was artichoke. It's a thornless cultivar called emerald, so the young leaves do look very much like Shastas but they're ever so slightly more severely toothed. This photo (I nabbed it off google) satisfied my skepticism and now I can't wait to watch it grow into the 5' tall, 6-8' wide monster it's supposed to be! I'm going to be putting it in a huuuuge planter so I can move it to shelter in winter. The planter is actuall a food-safe plastic muck bucket so I'm pretty sure it's big enough- at least 40 gal.
Now to plant asparagus!