Things You'll Need
Soil testing equipment
Disc and tractor
Pre- and post-emergent herbicides
Guide to walnut tree pests and diseases
Growing walnut trees gives farmers access to two types of crops: walnuts and lumber. It takes patience to grow walnut trees because it will be 12 years before walnut trees produce nuts and at least another 12 before trees can be harvested for lumber. Most harvesting doesn't begin until the trees are 25. After walnut trees are ready to be harvested for lumber, they have the highest return per acre of all trees used as timber crops. Walnut trees used for nut production have a lower return per acre — however when the trees are 25 they can be harvested for their lumber. Stagger the planting of walnut trees to ensure that as your stand matures you will have trees available for harvest every year and continuous nut production.
Growing Walnut Trees for Profit
Select land with fast draining, loamy soil with a pH between 5.0 and 8.0. For the most productive trees, the soil depth should be three feet.
Extension and State Agriculture labs will test your soil for a nominal fee. You can either borrow equipment from these offices or purchase your own. Take multiple plugs from different locations. Mix the plugs together and then submit them. This will give you a baseline for how fertile the soil is and what amendments will need to be added.
Using a tractor, disc the area in which you will plant the walnut trees. Remove all vegetation in the planting area.
Plant the walnut trees in early spring. For trees that will be used for nut production, space trees 18 x 18 feet apart. You are aiming for 25 to 30 trees per acre. For trees that will be harvested for lumber, space them 15 x 15 feet apart or closer. The closer these trees are planted to each other, the less pruning you will have to do. Aim for 75 to 100 trees per acre. Be prepared to lose approximately 25% of the saplings you plant.
Apply fertilizer every year: A nitrogen-based fertilizer will help the trees grow faster. Test your soil at least every five years to make sure the walnut trees have all the nutrients they need for optimum growth.
Apply pre - and post- emergent herbicides. You will want to apply herbicide every year.
Start pruning when trees are three years old. In the spring, while trees are still dormant, remove the lower branches so only the top 1/3 of the trunk has branches. You want the crown to be as wide as 1/2 the total height of the tree.
Start selectively harvesting walnut trees with a diameter of 6 - 10 inches. These trees are also called "pole" sized trees. Remove weak, misshapen, crowded or otherwise undesirable trees at this time. Commercial harvesting of walnut trees for lumber begins when they are 25 to 30 years old.
Walnut trees begin producing nuts when they are 12 years old. They should be allowed to bear nuts until they are 20 to 25 years old, when nut production falls off. You can harvest the trees for lumber at this time.
Walnut trees are susceptible to a number of insect pests, fungal and viral diseases. Inspect your trees weekly for signs of disease and pest damage. A guide of pests and disease will assist in identification. Contact your local county or state Department of Agriculture office for advice on prevention and treatment.
Walnut trees do well on North and East facing hill slopes. Walnut trees can also be planted as a hedgerow along the road sides of fields. Examine your walnut trees carefully for signs of insect damage or disease.
Do not plant walnuts in areas that are prone to flooding or have standing water.