Seeds from Morus nigra, Black Mulberry, Toot Tree or Persian Mulberry. Morus nigra, the black mulberry, is a species of flowering plant in the family Moraceae, native to southwestern Asia, where it has been cultivated for so long that its precise natural range is unknown. Morus nigra is a deciduous tree growing to 40 ft tall by 50 ft broad. The leaves are 4 to 8 inches long by 2 to 4 inches wide. The edible fruit is dark purple, almost black, when ripe, a compound cluster of several small drupes which is richly flavored, similar to the red mulberry Morus rubra but unlike the more insipid fruit of the white mulberry Morus alba. Black mulberry has long been cultivated for its edible fruit and is planted and often naturalized west across much of Europe, including Ukraine, and east into China. It has gained the Royal Horticultural Societys Award of Garden Merit. Zones 5 to 11