How to prevent twig dieback in young pomegranate trees in severe winter? Detailed explanation of cold protection methods

Twig dieback in young pomegranate trees refers to the phenomenon in which some branches shrink and dry out or die after the tree overwinters. In northern China, winters are cold and dry, early spring has little rain and much wind, and evaporation is high, while young pomegranate trees grow a lot each year and the pith of the branches has poor water retention. Therefore, in a severe winter, twig dieback is likely to occur. The techniques for preventing twig dieback in young pomegranate trees in severe winter are introduced below.

Variety selection

Choose varieties with relatively strong cold resistance, such as Hongpi Tian No. 1, Heizi Tian, Qingpi Tian No. 1, Juzi Mi, Taishan Hong pomegranate, Tunisian soft-seeded pomegranate, etc. Some varieties with very poor cold resistance cannot overwinter safely when planted in northern China.

Strengthen fertilizer and water management

For young trees planted for 1 to 2 years, during the growth period from July to September, apply more phosphorus and potassium fertilizer, control nitrogen fertilizer, and reduce the number of waterings, so that new shoots stop growing in time and the plants become fully lignified.

Timely pinching

In mid-August, promptly remove the growing points of new shoots to control the elongation growth of branches and promote nutrient accumulation. At the same time, promptly remove the young buds sprouting at the pinched sites of the branches to ensure that the branch tissues mature fully and enhance the plant's overwintering ability.

Chemical cold protection

In early August, spray 300 times diluted paclobutrazol on the leaves to control new shoot growth and promote branch fullness. In November, after the plants shed their leaves, apply petroleum jelly to the new shoots of the branches, which can significantly enhance the plant's cold resistance. From late February to early March of the following year, spray the tree canopy with 5% lime milk, which can delay the active period of the branch cambium and reduce water evaporation from the branches.

Earthing up for cold protection

For seedlings planted in the current year, generally in early November, bend the branches of the young trees down and cover them with soil to prevent the branches from losing water and freezing. The general soil covering thickness is about 30 cm, and in early March of the following year, release the branches from the soil again.