Growing black walnut trees can produce valuable timber and edible nuts. Using the black walnut seed, or nut, is perhaps the most cost-effective method for propagating the trees. Gather nuts from trees that have a good trunk structure and a large amount of kernel to the interior nut. All black walnut seed will require some form of winter stratification before they can be planted into a field the next spring. Typically this will require the nuts being stored at temperatures between 34 degrees and 41 degrees Fahrenheit for a period of 90 to 120 days.
Collect the nuts in the fall. Wear the rubber gloves to reduce dark staining to your hands.
Soak the black walnuts in a plastic bucket filled with water. This will soften the outer hull. Remove the hulls by hand. Place the hulled nuts back into the bucket full of fresh water. Discard the floating nuts. Keep the nuts that have sunk to the bottom of the bucket. These are to be planted the next spring.
Remove the sinker nuts from the bucket. Allow them to dry for 24 hours. Place the nuts in a plastic bag. Store the nuts in a refrigerator for 90 days to 120 days before spring planting.
Place a marker flag centered on a 12-foot-by-12-foot grid layout to identify the planting locations. This spacing will allow for a good tree growth with good nut production. The flags will also serve to identify the plants' location if the surrounding vegetation exceeds the new tree height during the growing season.
Dig the holes with the shovel to a depth of 6 inches to 8 inches deep, and as wide. Loosen the soil well with the shovel. Refill the hole with the loosened soil to a depth of 4 inches to 6 inches. Place two nuts in each dug hole. Cover the nuts with approximately 2 inches of soil.
Reduce predation to the nuts and young trees by keeping the planting holes 330 feet from wooded areas. If that is not possible, you may have to protect the nuts.