Causes and treatment methods of honeysuckle yellow leaves
As a vine with both medicinal and ornamental values, honeysuckle is popular in garden planting. However, the problem of yellow leaves often leaves growers helpless-the turning of leaves from green to yellow not only affects ornamental quality, but also weakens the plant's photosynthesis ability, resulting in a sharp decrease in the number of flowering. This article systematically sorts out the three main causes of yellow fever and corresponding treatment plans to help you accurately diagnose the root cause of the problem. Root suffocation: Survival crisis caused by stagnant water. The harmful mechanism of soil over-dampness. The root system of honeysuckle has villy-like absorbing root groups. When the water content of the cultivation substrate is greater than 70%, oxygen replacement is blocked and an oxygen-free environment is formed. Soaking for 3 days can cause necrosis of root hair cells, manifested by wilting new leaves and yellowing and shedding of old leaves. Demonstration of the four-step rescue process ① Immediately stop water and tilt the flowerpot to drain water;② Trim black and rotten root systems and retain healthy white roots;③ replace humus soil with perlite accounting for 30%;④ Use bamboo sticks to monitor soil moisture during the seedling stage. Nutritional imbalance: The two-way problem of fertilizer deficiency and fertilizer damage Identification map of nutrient deficiency disorders Nitrogen deficiency is manifested as the base yellowing spreading upwards. When phosphorus is insufficient, the veins are purplish red. When potassium is lacking, the leaf margins are scorched. Typical symptoms are thin and light-colored new leaves, accompanied by thin branches and elongated internodes. Precise fertilization schedule Apply decomposed sheep manure (500g/plant) during the germination period, apply potassium dihydrogen phosphate (800 times solution) during the bud period, and supplement balanced compound fertilizer (15-15-15) after flowering. Pay special attention to the principle of "applying thin fertilizer frequently" in high temperature seasons to avoid EC values greater than 2.0mS/cm. Pathogen invasion: Prevention and control system for fungal disease identification guidelines white powder appears on the back of the leaves at the beginning of powdery mildew, and forms a yellow halo after 7 days; leaf spot disease originates in the middle of the leaves, producing brown concentric rings. Both can lead to the destruction of photosynthetic tissue and cause systemic yellowing. Biochemical collaborative control found that the diseased leaves were immediately removed and buried deeply, and a biological agent of Bacillus subtilis (10 CFU/g) was sprayed on the morning of sunny days. In severe infections, 25% pyraclostrobin (1500 times) and 40% difenoconazole (3000 times) were used alternately, with application intervals of 7-10 days.
By establishing a three-level response mechanism of "observation-diagnosis-intervention", the yellow leaf problem of honeysuckle can be effectively controlled. It is recommended to carry out basic maintenance such as leaf cleaning and soil moisture testing every month, and clear drainage ditches before the rainy season. The annual tip length of healthy honeysuckle plants can reach 2-3 meters, achieving dual improvement in medicinal and ecological values.