09-06-2010, 06:04 AM
I have a mature orchard of Dancy tangerines: 20 feet apart is just right. I don't know about red mulberry, but I have 2 black mulberries, and it could well be that the growth habit is similar. They don't get very tall, but have a widespread canopy. The branches can hang down to the ground - almost like a weeping willow. Be prepared to prune it regularly or its spread will encroach on paths or nearby plants. It does take well to pruning, and you can root the cuttings successfully.