After researching all day & driving my husband crazy, I do believe that these are indeed plum grannies. I picked a small bowl-full and set them on my kitchen table & oh my! my house smells like honeysuckles! I probably won't be slicing these up (although I have no doubt they'd prob make amazing pickles, as odd as that is lol) but I am so delighted they decided to grace my yard! What a wonderful discovery!
