In my yard I grow wild ones which I assume are M. rubra but I guess they could be hybrids, and I have a 'Wellington' which has very good flavor and large berries, an 'Illinois Everbearing' which has slightly smaller berries but with excellent flavor and a long fruiting season (though not ever bearing). My trees are small and I only get a half gallon of berries off of all of them combined. I have some trees that I grew from seeds that someone gave me saying that the trees were small bush form with purple, sweet berries. Last year one of them fruited and the berries were large and white without any berry flavor, just sweet as sugar. Most of the collection is starting to flower now and one more of the seedlings is flowering so I will wait to see if it has white fruit, hopefully they will have berry flavor instead of just being sweet. So far this collection of mulberries has been a highlight of my garden, I would plant more of them if I had more room.