We’re not sure if this may be ‘Giraldi’ which grows to about 6-10′ or ‘Issai’ with a similar height. ‘Giraldi’ is supposed to be a hybrid between our native red mulberry, M. rubra and white mulberry, M. alba. The fruits are similar to another hybrid mulberry, ‘Illinois Everbearing.’ ‘Issai’ is a cultivar of white mulberry. It’s also possible that this is an entirely different variety.
It should be cold hardy in the ground in our area, or grow in a container that you bring in under protection for the winter.
Mulberries are fast growing and precocious bearers. However, you need to protect them from deer.