After two or three years, you only need to water the trees at the hottest time of the year or during the drought, about once or three times a month.
2. Treat weeds. Keep the seedlings free of turf and weeds in order to compete with the seedlings and protect them. Remove turf and weeds by hand, or lay a fabric weed barrier. Larger seedlings can be treated with mulch, leaving weeds about 2 or 3 inches from the roots.
Don't use mulch for plants that don't sprout from the soil, because mulch will prevent new buds from growing. Wait until the seedlings grow vigorously and grow roots.
3. Learn about pruning walnuts. If you want to plant walnuts as wood, it is very important to prune them as early as possible to ensure that the trunk is straight, and leave a "faucet" branch at the top of the tree to guide them to stand upright in the next one or two growing seasons. You can keep the saplings as nuts until they become thinner, but it is wise to prune the black walnut trees afterwards, because they are usually sold as timber or even nuts.
If you haven't pruned trees before, especially saplings, I suggest you find an experienced pruning machine to help you identify leaders and important branches.
If the top of the tree is forked, bend the best guide rod at right angles and tie it to other branches as support, and then cut off the top of the supporting branch to prevent growth.
4. Sparse the location of trees to choose the best example. Most orchards began to grow plants that were beyond the local capacity. When the trees are big enough to make the branches collide with each other, please choose the healthiest tree to show the characteristics you value, usually the trunk is straight and grows rapidly. Remove the rest, but avoid clearing too much space to prevent weeds and even compete with the growth of trees.
Fertilize the trees immediately after they are covered by saplings. At least for black walnut, fertilization is still controversial, because if the soil is already rich in nutrients, fertilization can promote the competition of weeds more than trees. Wait until the suitcase is as big as a pole, or at least 4 inches in diameter and 4.5 feet off the ground. Ideally, soil or leaves should be sent to a forestry laboratory to determine the exact nutritional deficiency. If this is not possible, please apply fertilizer containing 3 pounds of nitrogen, 5 pounds of calcium superphosphate and 8 pounds of potassium carbonate to each tree in late spring. Leave a few unfertilized trees to compare the effect. If it is positive, it should be reapplied every 3-5 years.
After fertilization, test the pH value of the soil to see if it needs to be restored to normal level.
6. Control pests. Squirrels are common in walnut forests. If left unchecked, squirrels can eat a whole nut. Cover the trunk with plastic tree cover to prevent them from climbing. If possible, trim branches less than 6 feet from the ground, and don't cause knots that will reduce the value of wood. Other pests, such as caterpillars, aphids and flies, vary from region to region. If they are active in the late growing season, they may not harm your tree. Ask a forester or an experienced walnut grower nearby for information about your area.