bareroot hosta from Easy to Grow Bulbs and that went well, so I am hopeful this order will also go well. You can be sure I will report back if it doesn't. They gave me a $5/off referral code if anyone else is interested in ordering from them.
I've been studying lists of plants that survive under black walnuts and tolerate shade, but I've found quite a few conflicts, so I'll just have to try some plants and see which make it. I ordered some blue blanda anemones which are new plants to me, but they're supposed to survive under black walnuts so I'm giving them a try.
white bleeding heart and a white astilbe (also new to me).
I'm seriously considering ordering more irises from Schreiner's. Irises are another flower that can grow under black walnuts, but I'm not sure they'll get enough sun. I should probably wait until plants reemerge in spring and see how much space we have left before I order any more.