Before you can crack black walnuts, you must first remove the hulls. Hulls, or husks, are the green outer coatings of black walnuts that turn yellow as they begin to ripen in the fall. By removing these hulls immediately after harvesting, you will preserve the color and flavor of the nuts. Although the nuts can be cracked once they've been dehulled, you should soak them before cracking them to make the shells softer and less prone to shattering.
Fill a large bucket or tub with water and add the hulled walnuts.
Rinse the walnuts thoroughly to remove juices and hull debris. Wear rubber gloves while doing this to avoid staining your fingers with the juice.
Discard the nuts that float. Floating nuts indicate that the shells are empty or partially filled.
Spread the walnuts on a clean wire screen to dry. They should not be layered more than three nuts deep.
Place the wire screen and nuts in a dry, cool, well-ventilated area. Allow the nuts to thoroughly dry for two to three weeks.
Soak the black walnuts in water for one to two hours prior to cracking.
Place a walnut on a flat surface, pointed-side up.
Hit the top of the walnut with a hammer until it weakens and splits along its axis.
Pry the nut meat from the shell using a pick and pliers.