Management methods for woody medicinal plants after frost damage

PruningLeaf drop after frost is a self-protection measure by which the woody medicinal plant resists frost damage; shedding leaves reduces abnormal water loss and prevents the tree from dying due to excessive dehydration. Leaf drop after frost delays sprouting, so you must wait until the branches sprout and dead branches can be distinguished, then promptly prune out dead branches and diseased or pest-infested branches, keeping as many living branches and remaining leaves as possible; branches whose death or survival is still hard to determine can be pruned in several rounds. The pruning amount should be light, the cuts should be smooth, and large cuts should be disinfected with 75% alcohol or 0.1% potassium permanganate and wrapped with plastic film.

FertilizingThe medicinal plants' vigor is generally weakened, and the root system of frost-damaged plants has a poor ability to absorb water and nutrients. Therefore, after woody medicinal plants suffer frost damage, root topdressing should be carried out; fertilizing should be done lightly, in thin doses, and multiple times, to promote the growth of sturdy new shoots and help restore plant vigor, with quick-acting nitrogen, phosphorus, and potassium fertilizers as the main type. After new shoots appear, foliar spraying of fertilizer is preferable.

Pest and disease preventionFreezing easily causes branch damage and leaf drop, leaving branches and trunks exposed, which can readily lead to relatively serious pests and diseases later, such as resin disease and sunscald bark cracking. Therefore, after frost, diseases and pests should be prevented and treated promptly; for disease control, agents such as Bordeaux mixture and carbendazim can be used, and for pest control, agents such as dichlorvos and trichlorfon can be used.