In a 4-quart slow cooker, stir wheat berries, cinnamon stick, orange zest, ginger, nutmeg, allspice, cloves, salt, butter and 4 cups water until combined. Cover and cook on low for 6 to 8 hours or on high for 3 to 4 hours. Remove and discard ginger and cinnamon stick. Stir in molasses. Divide among 6 bowls; top with raisins and pecans before serving, if desired.