All “beauty” graphics aside, I believe that the heirloom purple potatoes available in farmers markets are about as close to “poisonous” nightshade one could get - the hybridization is that extensive and watered-out.
My wife cannot eat the heirloom-purples; severe and debilitating indigestion (Upper-GI stress).
I grew a ton of purple taters this year. Very good yield. Also a bunch of russets and the Pontiac reds.
But the BEST eating taters I got was a bunch of finger potatoes! Wonderful eating! Problem is, they don’t get very big, so you need to plant them pretty dense to get a good amount.
I need to save as many as I can for seed potatoes. Regular, plain old vanilla seed potatoes were $1 a pound at the Ag shop last spring.
Fingerling seed potatoes were $4.
I didn’t buy any, all I got this year came up from last years leftovers.