For longest preservation and best flavor, dry black walnuts after harvesting. When harvested from the tree, black walnuts have a thick hull surrounding the shell that covers the nut meat. Removing the hull immediately after harvest prevents the hull from tainting the flavor of the walnuts inside. After hulling, allow at least one to two weeks for proper drying of your black walnuts.
Put a pair of work gloves on when handling black walnuts in their hulls to prevent the hulls from staining your skin.
Hold a black walnut with the hull between the teeth of pliers and tap the hull with a hammer to crack it.
Pull the cracked hull off the walnut with your gloved hands and drop the walnut into a bucket of water.
Hull the remaining walnuts until all of them are in the water.
Swirl the walnuts in the water with your hand to allow the water to remove any bits of hull still adhering to the shells.
Pour out the water, leaving the walnuts in the bucket.
Scatter the walnuts into a single layer on a wire screen.
Set a second wire screen on top to keep birds away from the walnuts.
Place the wire screen drying apparatus in a well-ventilated location for up to two weeks until the shells of the walnuts feel dry.
Crack the shells of the black walnuts with a nutcracker to access the nut meat.