Mulberry Rhubarb Liqueur I made Mulberry Rhubarb Liqueur last summer when rhubarb and mulberries were in season. I buy my rhubarb at my favorite farm, Nicolet Farms, located on Hwy 64 in Suring WI. If you are privileged like I am and have a son and daughter-in-law that have not one but three Mulberry trees