If anybody is considering a mulberry to grow because they want the fruit, I would highly suggest getting a known female tree from a nursery, a variety that has been breed for fruit. There are places that sell them mail order as dormant, bare root. You have to order at the right time, which of course now is not. I got mine from Burnt Ridge Nursery, I think they are in Oregon, they have several varieties. I don't know how you get any fruit from a tree, the wild birds would clean me out if the tree wasn't in my covered garden, but the tree is getting too big for the garden so I don't know what I'm doing to do with it.
If you start from seed, you wait several years just to see if you have a female or not--a lot of wasted time. I think you can also start one from a cutting, that might be an option to get a cutting from a known female tree that has fruit you like. Some of the varieties are stainless--white or pinkish fruit, not the purple that stains everything. I love mulberries, grew up with them in PA where they grew wild, we had a huge tree that was in the cow pasture across the fence--not on our property but on big King Ranch property that we treated like our own. That tree could have been a record size for a mulberry, it was huge, a whole herd of steers used to fit under it. I went back years ago to visit it and it was gone. My brother said it was cut down. Why anybody would do that is beyond me, what a travesty.