A Detailed Explanation of Walnut Propagation Methods and Key Technical Points

Walnut is a common nut in daily life. Because of its extremely high nutritional value and unique taste and flavor, it has gained consumer recognition, and more and more farmers are growing walnut trees. Below, the editor will introduce the propagation methods of walnut.

1. Propagation by sowing

The collected seeds are sown in spring, or sown in autumn, when the temperature is suitable. In spring, March and April are the best sowing periods. The seeds must undergo stratification to promote germination before sowing; direct sowing rarely germinates. The stratification site should be a warm, sunny place, and generally one layer of sand and one layer of seeds are used, maintaining a temperature of 2°C to 5°C. The humidity should be around 60%. After two months of stratification, they can be taken out and sown. Therefore, stratification must be carried out in advance. Alternatively, before sowing, soak the seeds in cold water, soak and press them, changing the water once a day. After a week, expose them to the sun until the shells crack, and then they can be sown. Sow in holes, place the seeds horizontally, cover with about 6 cm of soil, then water and manage them.

2. Grafting for seedling raising

Generally, hickory is used as the rootstock. Wild hickory has strong adaptability, strong resistance, and sturdy stems. Grafting other varieties can bring fruiting earlier. For the scion, select one-year-old healthy branches with moderate internode strength and no pests or diseases from vigorous mother plants of excellent varieties. If there are many scions, they can be stored in wet sand. The rootstock is required to have a thickness of about 1.5 cm, and grafting is done at a position about 10 cm above the ground. After cutting, grafting must be done immediately; bleeding affects survival, and the scion can be placed in the mouth to prevent bleeding. The cleft grafting method is generally used. After fixing, check frequently, and remove the film after survival.

3. Propagation by cuttings

Generally, cutting is the fastest method to produce seedlings. Cut one-year-old to 3-year-old branches from the outer part of the mother plant, requiring branches with a thickness of 1.5 cm. The cut branches should be about 15 cm long, and some trimming is also needed, so that finally about 10 cm of branch is used for cutting. Three to four leaves should be kept on the upper part of the branch, then the lower end can be soaked in a rooting powder alcohol solution, after which it is inserted into a moist seedbed, covered with pine needles to keep warm, and shaded with a sunshade net, controlling the temperature between 18°C and 25°C, not exceeding 30°C, and not lower than 10°C. Later maintenance is also needed.

The common propagation methods of walnut include sowing, grafting, and cutting. They are not easy to carry out, so more methods are needed to help with propagation. However, these three methods each have their own advantages, and everyone can decide according to the actual situation.