Nutritious Black Walnut Pieces - Two 14 oz. Bag What are the differences between Black walnuts and English Walnuts? There are 3 key differences. First, Black Walnuts are a wild, hand-harvested nut, while English walnuts are grown in orchards. Second, Black Walnuts have a very thick shell, making them tough to crack. Due to that reason, Black Walnuts are only available in various piece sizes. Third, the flavor of the 2 nuts is very different. English walnuts have a mild flavor. Black Walnuts have a bold, distinctive earthy flavor derived from the roots of the tree. They are primarily used as an ingredient in many recipes and are also popular in ice cream. What is the best way to Store Black Walnuts? Generally speaking, we recommend consumers store Black Walnuts in the refrigerator up to a year, or the freezer for a year or longer. This will ensure your Black Walnuts maintain freshness and best flavor.