The contrasting colors of mango and boysenberry are lovely. If you like, serve the sorbets in frozen "mango boats," made by scooping out the centers of halved mangoes and freezing the shells.
Note:
If you do not have an ice cream maker, you can turn this mixture into a granita — an Italian frozen dessert. Mix an additional 1 cup water into each sorbet mixture. Freeze separately until semifirm, whisking occasionally, about 3 hours. Cover and freeze until solid, at least 6 hours or overnight. Using fork, scrape surface of each granita to form crystals. Scoop boysenberry and mango crystals alternately by 1/4 cupfuls into frozen mango halves or glasses and serve.