Common Diseases in June and Their Prevention
With the arrival of hot and rainy weather in summer, various plant diseases enter a high-incidence period. This article focuses on the frequent occurrences of powdery mildew, pear-cypress rust, and other typical diseases in June, combining years of garden maintenance experience to systematically sort out identification features and scientific control measures.
Comprehensive Control Plan for Powdery Mildew
Symptom Identification Features
Mainly危害 rhododendron, boxwood, and other shrubs, initially presenting as white powdery mold on both sides of the leaves, which can cause leaf curling, deformation, and premature defoliation, affecting photosynthesis in the plant.
Environmental Conditions for Onset
The optimal temperature for onset is 18-25°C, and spores spread rapidly when the air humidity is over 70%. Particular vigilance is needed during the plum rain season for collective outbreaks.
Chemical Control Strategy
Use 15% flusilazole 800 times liquid spray in the early stage, combined with pruning diseased branches to enhance ventilation. It is recommended to apply the medicine on sunny mornings, with a 7-day interval for 3 consecutive sprays.
Control Guide for Pear-Cypress Rust
Typical Symptom Manifestation
Orange-yellow vesicular protrusions appear on the leaves of蔷薇科 plants such as Japanese quince and pear trees, and later, the lesion breaks to release rust-colored powder, causing the leaves to turn yellow and fall prematurely.
Pathogen Transmission Pathways
Spread by wind-borne winter spores, with cypress trees acting as intermediate hosts. The risk of transmission significantly increases when the precipitation is >200mm from April to June.
Cross-Control Plan
Alternately use 20% flusilazole 1000 times liquid and 12.5% myclobutanil 1500 times liquid, focusing on spraying the back of the leaves. It is recommended to clear the surrounding cypress trees.
Disease Prevention and Management System
Ecological Regulation Measures
Keep plant spacing at 80cm or more, use drip irrigation technology to control humidity, and apply decomposed organic fertilizer every quarter to enhance plant disease resistance.
Monitoring and Early Warning Mechanism
Establish a weekly inspection system and equip with temperature and humidity recorders. Start preventive spraying when the average humidity is >75% for 3 consecutive days.
Through scientific identification of symptom features, precise grasp of control timing, and the combination of physical and chemical control methods, June's high-incidence diseases can be effectively controlled. It is recommended to establish a full-year maintenance log, combined with meteorological data to develop dynamic control plans.