Which black mulberry (morus nigra) tastes best?

[californicus]

Here is some info on how to tell M. Nigra from the buds

Morus nigra or not? Looking at the buds

As many know, it’s not easy to find a true Morus nigra at the trade. A lot of places sell black-fruited mulberries as M. nigra, which they are not. Even before you have a chance to see and taste the fruit, take a look at the buds. Morus species are named according to the color of their buds, not fruit. Nigra means black buds, alba means white buds (not truly white as a white paper, of course, they are pale beige to pale brown). The twig on the photo below is of the variety named Sicilian Black …

At least from what I read here, not all varieties sold as M. Nigra (by DWN and others) are actually labelled correctly. I got mine (Noir de Spain) from Whitman farms and it was labelled correctly. A cheaper alternative is to root a M. Alba cutting and graft M. Nigra on it (which is pretty much how M. Nigras are sold).