What are the prevention and remediation measures for walnut freeze damage?

Walnut is one of our common nuts. Walnut likes light, is cold-tolerant and drought-tolerant, but the current-year seedlings of young trees have high water content and low cold resistance. In winter or during frost seasons, freeze damage and early-spring shoot dieback severely affect the growth and development of the plants, and in severe cases cause the plants to die. So how should walnut freeze damage be prevented? And how should it be remedied? Let's take a look.

I. Prevention measures

1. Fertilization

Before July, mainly apply nitrogen and potassium compound fertilizer, while after July, apply compound fertilizer based mainly on phosphorus and potassium fertilizer. In addition, increase the application of trace elements such as calcium and boron. This readily promotes the full maturity of branches and buds, thereby enhancing the cold resistance of the plants.

2. Watering

After the walnut blooms and sets fruit, there is relatively little precipitation, so water once at this time. When the rainy season arrives, do a good job of water control for maturity, to ensure the plants stop growing in time. Before the soil freezes, water once with freezing water to increase soil moisture, which can slow the rate at which soil temperature drops and allow the plants to overwinter safely.

3. Proper pruning

Pruning of young trees is mainly for shaping, so that they quickly form a crown, while pruning of old trees is to regulate the relationship between growth and fruiting, thereby increasing walnut yield and quality. But from the perspective of preventing freeze damage, in addition to conventional autumn pruning, summer pruning should also be emphasized, pruning away some water sprouts and dense growth to increase air and light penetration, so that branches and buds grow more robustly.

4. Spraying protective agents

Before the onset of winter or in early spring, a low-temperature protective agent can be sprayed on the plants, which can enhance the cold resistance of the plants, with relatively good results.

II. Remediation measures

After the beginning of spring, promptly prune away branches killed by freeze damage. The wounds after pruning should be coated with a chemical agent to prevent pathogens from invading and causing rot. In addition, after pruning, strengthen fertilizer and water management to restore tree vigor as soon as possible. Before planting and bud break, thoroughly spray thiophanate-methyl solution or Fubiqing emulsion, which can sterilize and prevent the plants from being invaded by pathogens when their resistance is low. For branches that have already rotted, in mild cases the old bark can be shaved off and then brushed with the agent; for more severe symptoms that have rotted to the xylem, the diseased scar can be cut away along the outer edge of the lesion to make it spindle-shaped, then apply the agent, scrape off the lesion, or burn the diseased branches.

The above are the prevention and remediation measures for walnut freeze damage. I hope they can help you. To learn more related knowledge, please stay tuned to us.