Latest Prevention and Remedial Measures for Walnut Frost Damage

Walnut is one of the nuts we commonly see. Walnut likes light, tolerates cold and drought, but the annual seedlings of young trees have high water content and low cold resistance. In winter or frost seasons, frost damage and early spring branch shrivelling severely affect the growth and development of the plant, and in severe cases cause the plant to die. So how should walnut frost damage be prevented? And how should it be remedied? Let's take a look.

I. Preventive Measures

1. Fertilization

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

2. Watering

After the walnut blooms and bears fruit, there is relatively little precipitation, so water once at this time. When the rainy season begins, control water to promote maturity, so as to ensure the plant stops growing in time. Before freezing, water once with freezing water to increase soil moisture, which can delay the speed of soil temperature dropping and allow it to overwinter safely.

3. Proper Pruning

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

4. Spraying Protective Agents

Before winter or in early spring, low-temperature protective agents can be sprayed on the plants. This can improve the cold resistance of the plants, and the effect is relatively good.

II. Remedial Measures

After spring begins, promptly prune away branches killed by frost damage. The wounds after pruning should be coated with medicine 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, comprehensively spray thiophanate-methyl solution or Fubiqing emulsion, which can play a sterilizing role and avoid the plant being invaded by pathogens when its resistance is relatively low. For branches that have already rotted, for mild cases, scrape off the old bark and then brush with medicine. For more severe symptoms that have rotted to the xylem, cut off the diseased scar along the outer edge of the lesion to make it spindle-shaped, then apply medicine, scrape off the diseased spot or burn the diseased branches.

The above are preventive and remedial measures for walnut frost damage. We hope they can help you. If you want to learn more related knowledge, please stay tuned to us.