I grew them in my garden one year. Fun fact: if you have ever thought: "But self, where will I find a million aphids on a Sunday evening?" the answer is "on an artichoke." I had never before had a problem with aphids. I had never seen aphids in my garden. Two artichokes later: two million aphids.

They took up about three square feet of my garden, and produced, in total, about three ounces of edible material.

I mean, parsley doesn't produce much edible material, but it also doesn't take up a square foot per ounce.