Just thought I'd introduce myself. My name is Greg (4734 on your phone). I live about 30 miles west of Tulsa OK. I grew up in North Central Oklahoma. I've always liked cactus and other desert plants. I keep hardy cactus outdoors and have a few tropical and sub-tropical that I take in come wintertime...

May I suggest Escobaria vivipara for the second?

New here, but not to cactus. I live in Oklahoma. As far as zone 5a you might try looking at bonap (biotics of North America plants) and get an idea. That's what I did. Other species: I've found Escobaria missouriensis in Montana. Echinocereus triglochidiatus in Colorado. Cylindopuntia imbricata, lep...