How to Safely Overwinter Young Cherry Trees? A Detailed Guide to Management Measures
Although the survival rate of planted cherry saplings is high, young trees find it difficult to safely pass the harsh winter. Because the branches of young trees are not very winter-hardy, they become dehydrated, shriveled and dried out, a phenomenon commonly known as "shoot dieback." Winter shoot dieback in young cherry trees is fairly common, occurring to varying degrees in most years. In mild cases it causes the tree form to become disordered and hinders early fruiting; in severe cases the entire tree dries up and dies. Eight technical measures for safely overwintering young cherry trees are introduced here for use in various regions.
1. Spread ash and shallow tillage. Wood ash can be spread over the whole orchard and turned into the soil with shallow tillage, which loosens the soil, absorbs heat and preserves warmth, reduces frost damage, and also provides the young trees with various mineral nutrients such as potassium, phosphorus, calcium and silicon. Generally, spread 300 kg of wood ash per mu and shallow-till 3-5 cm.
2. Bend the trunk and bury it in soil. After 1-2 year old young trees have dropped their leaves and entered dormancy, bend the trunk and bury it firmly with moist soil to prevent the branches from being exposed and losing water. The depth of soil covering the trunk and branches is about 30 cm.
3. Irrigate with freezing water. Irrigate with freezing water 5-6 days before "Minor Snow," which has a certain effect on cold resistance and frost prevention. After irrigation, when a person can walk on the ground, lightly scratch the soil to cut the soil capillaries.
4. Build a soil barrier at the root crown. Before the soil freezes, build a crescent-shaped soil barrier 50 cm high on the northwest side of the tree, 30 cm from the trunk, which can effectively prevent the root crown from freezing and shoot dieback.
5. Whitewash the trunk. In winter, mix quicklime with water to make a lime slurry, add a small amount of salt, and apply it evenly to the trunk. This can reflect more sunlight and prevent damage caused by large day-night temperature differences.
6. Cover with plastic film. The roots of young trees are generally concentrated in the soil layer 20-30 cm below the ground surface. Covering with plastic film has a certain warming effect on the shallow soil.
7. Winter-prune secondary shoots. In winter, prune off the secondary shoots that transpire heavily, and apply petroleum jelly (a protective agent) to the cut surfaces to reduce water loss.
8. Wrap with film. Cut white agricultural film 0.03 mm thick into strips 3-5 cm wide and 1-2 m long, then gradually wrap the scaffold branches and main trunk along the direction from the shoot tips toward the base and from the upper part of the trunk downward. Wrap tightly and completely without exposing the bark, which can play a positive role in protecting the bark.