Black walnuts are a flavorful ingredient that many people like to add to breads, cakes and other baked goods. They can also be eaten raw. If you would like to grow and harvest your own black walnut trees (Juglans nigra L.), they are best planted from seed (the walnuts). Black walnut trees prefer full sun and can be planted in the fall or the spring, although most home gardeners have more success when planting them in the fall.
Prepare the soil two to three years before planting black walnuts. Till the soil the about 12 to 18 inches deep and incorporate 25 percent of organic matter, such as compost, into the soil. Repeat this in the fall and spring until planting time.
Gather the black walnuts when they drop in the fall. It is not necessary to remove the husk or shell.
Keep the walnuts dry for a fall planting. Stack the nuts together in a pile--no more than 15 inches high--and in a shady area until you are ready to plant them.
Alternatively, stratify the nuts for a spring planting. Set the nuts in a single layer on the ground in an area protected from wind and animals. Then, cover them with 2 inches of moist sand or moist leaves. If necessary, have a second layer of black walnuts, which should be covered with another layer of sand or leaves. Plant the walnuts in early spring before they sprout in the their temporary location.
Plant the walnuts 4 inches deep. If you are planting more than one walnut, use your hoe to create a 4-inch trench (also called a furrow). Space walnuts at least 4 feet apart and trenches 10 feet apart from one another. Alternatively, to grow a clump of walnut trees, evenly plant 6 to 10 walnuts in an area that is 16 to 18 feet in diameter.
Backfill the soil with your hoe to cover the walnuts with about 2 inches of soil. Do not level the soil with the ground so it will hold excess water after rainfalls and waterings. Black walnuts like lots of water.
Water your seeds with about 2 inches of water and keep the soil moist at all times, watering them well when rainfall is scarce.