The most common way to introduce walnut trees to your yard is by planting saplings, but it is also possible to start the trees from seeds. It is not a complicated process, although the seeds do require some special care prior to planting. Propagating walnut trees this way also requires patience, as it can take from four weeks to one year for the seedlings to emerge. Despite the time it takes, growing walnut trees from seeds can be a very interesting project for any gardener who enjoys a bit of a challenge.
Collect walnuts that have fallen from the tree in autumn. Use a sharp knife to remove the hull from the walnut. Place the hulled walnuts into a bucket of water to rinse them clean. Examine the nuts and discard any that rise to the top of the water because they are not likely to germinate.
Place the walnuts into a container and cover them with 3 inches of moistened sand. Place the container into the refrigerator and allow it to remain there for 120 days. Check the sand regularly and add moisture as needed.
Prepare the planting site by removing all grass, weeds and rocks. Plant between three and five walnuts in each spot that you would like a mature tree to grow. The nuts should be planted 2 inches deep. Cover the area around the planting site with a 2-inch layer of straw to control weed growth.
Water until the soil is moist, but not soggy, after planting. Continue to add moisture if your area experiences long dry periods, as the seeds are less likely to germinate in very dry conditions.
Fertilize the young trees in July with 1/4 cup of slow-release fertilizer.
Examine the seedlings at each planting site once they have become established. Remove all but the healthiest of the seedlings by cutting them off where the stem joins in with the roots.