Black walnuts are a great nut if you clean and cure them properly. The walnuts can be air-dried by spreading in a single layer in a sunny location or they can also be placed in a mesh bag like an onion sack and hung up to dry. How To Make Dry Black Walnut Powder Hunker Black Walnut Benefits Walnuts Black Walnut Tree This natural drying process may take one to several weeks. How to dry walnuts . While the oven heats lay the walnuts on a baking sheet you can line it with foil or. How to Toast Walnuts on. Black walnuts have a hard shell. Spread the walnutson the mesh sheet that comes with the dehydrator. Regardless of which indoor method you use expect your walnuts to need at least two weeks to dry. We keep ours in five gallon or one gallon buckets with lids. Then place the slabs in a shaded area that has good air flow and stack them with 34 inch thick stickers spaced 20 inches apart to allow airflow between each slab. Be careful not to leave them on the stove too lo...