They're not grown in SIPs, much less on a rooftop. Heirloom? I have no idea.
There's something appealing about walking over to a neighbors house (Thanks Claude!) and shaking her Mulberry tree for dessert. The only real work involved is picking out a few twigs from the takings.
They are delicious eaten plain, topped with yogurt, or in a simple tart.
H2 and I spread out an old bedsheet under the tree and Art shook the branches with a pole.
On a related note, I'd like to thank Art and Chel at Pleasant House for reminding me that Juneberries/Serviceberries are edible. Add to that bit of info the fact that I've got one growing in my sideyard...........