What Causes the Leaves of Osmanthus Trees to Fall
As one of the top ten famous flowers in Chinese tradition, the abnormal defoliation of osmanthus trees often causes concern for those who care for them. This article systematically analyzes the four core factors that lead to leaf shedding and provides highly operable solutions to help you quickly identify the root causes of the problem.
I. Leaf Shedding Issues Caused by Root Damage
1.1 Typical Symptoms of Root Rot due to Waterlogging
When soil moisture continuously exceeds 70%, the osmanthus roots will show symptoms of respiratory obstruction. Initially, the leaf edges turn yellow, and later, the entire leaves fall off. Emergency treatment needs to be分级 intervention based on the degree of waterlogging: mild waterlogging can be addressed by loosening the soil and using an electric fan for forced ventilation, while severe cases require replacing the substrate with a permeable matrix containing 30% perlite.
II. Biosecurity Management System
2.1 Guide to Identifying Disease Types
(T-J) disease is common during the plum rain season, with round brown spots appearing on the leaf surface; sootycrust disease often occurs with aphid secretions. Control requires a three-phase treatment: initially removing diseased leaves → in the middle stage, spraying with benomyl → in the later stage, supplementing with seaweed fertilizer to enhance resistance.
2.2 Integrated Pest Management Plan
Red spiders爆发 in dry environments, with a silk-like web structure visible on the leaf back; scale insects attach to branches and stems to absorb sap. It is recommended to use a physical control combination of sophora alkaloid and diatomaceous earth, with monthly twice leaf back cleaning to reduce the probability of pest infestation by 80%.
III. Strategies for Correcting Nutritional Imbalances
Excess nitrogen fertilizer causes new leaves to curl and old leaves to develop burnt edges; excessive phosphorus and potassium lead to brown leaf veins. It is suggested to implement the "Three-Week Repair Method": in the first week, flush with a large amount of water → in the second week, add EM bacteria → in the third week, apply fulvic acid conditioner. Follow the principle of "applying thin fertilization frequently" in daily maintenance, applying diluted organic liquid fertilizer (1:1000) monthly in spring and autumn.
IV. Optimization of Light Environment
From 10:00 to 15:00 in summer, a 50% shading net is needed for protection, while in winter, full sunlight can be accepted. If sunburn (white burn spots on the leaf surface) has occurred, immediately transfer to a scattered light environment and spray with a 0.1% ferrous sulfate solution to promote chlorophyll regeneration.
By establishing a complete maintenance system of "prevention-diagnosis-treatment," the issue of osmanthus tree leaf shedding can be effectively controlled. It is recommended to record the leaf condition monthly and adjust the watering and fertilizing plan according to seasonal changes to keep the plant in the best growth state.