Walnuts can be grown in almost any soil conditions. They grow to be large trees, with large, leafy canopies that provide shade as well as delicious nuts. If growing for shade and for looks, trees should be spaced 40 feet apart so their canopies can form a pleasing arch. If walnut trees are being grown for lumber, space them 30 feet apart in order to grow more perfect trunks. Start your walnut grove by acquiring several walnuts of the variety you wish to grow. Collect walnuts in the fall, around the time of the first frost in your area, when nuts should be dropping from the trees.
Collect walnuts as they fall to the ground. The walnuts themselves will be inside of a husk which will be light green, yellow, brown, or black in color. Pick up several walnuts at this point.
Remove the husk from several walnuts, wearing gloves. In some cases the husk can be cracked and rubbed off with your fingers—in other cases use the side of a hammer to tap the hull until it cracks, at which point it can be pulled and rubbed off with fingers. Always wear gloves as the husks contain a brown dye that will stain fingers.
Place the nuts inside a plastic baggie, seal it, and place the baggie in the vegetable bin of your refrigerator until spring. This is known as stratification.
Remove the nuts from the refrigerator in spring, around the time of the final frost in your area. Soak the nuts in a bowl of water for 48 hours. Discard any that float, keep those that don't.
Choose a sunny location in your garden or yard. Loosen the soil for 6 or 8 inches in all directions and then plant your walnut approximately 1 inch below the soil. Mark the location so you don't mow any emerging trees.
Water the nut well and keep the soil damp but not soggy. Within 14 to 28 days you should see your walnut seedlings. After seedlings sprout, reduce water to once per week except under extreme heat or wind conditions. Allow soil to partially dry between waterings, but do not allow soil to become completely dry. Do not fertilize. Excess nitrogen could cause root damage or cause seedlings to grow too fast and become thin and spindly. Protect seedlings from rabbits and deer with wire fencing or by some other means.