How to Control Powdery Mildew on Cut Roses
Powdery mildew is one of the most important diseases of roses, damaging leaves, tender shoots, flower buds and flower stalks. The control methods are as follows: strengthen cultivation management and promptly remove diseased plant debris; prune promptly to improve ventilation and light conditions; do not apply too much nitrogen fertilizer, and appropriately increase phosphorus and potassium fertilizer. Chemical control: when disease occurs during the growing period, spray 15%...
Powdery mildew is one of the most important diseases of roses, damaging leaves, tender shoots, flower buds and flower stalks. The control methods are as follows:
Strengthen cultivation management and promptly remove diseased plant debris; prune promptly to improve ventilation and light conditions; do not apply too much nitrogen fertilizer, and appropriately increase phosphorus and potassium fertilizer.
Chemical control: when disease occurs during the growing period, spray 15% triadimefon wettable powder at 2000-4000 times dilution or 50% thiophanate-methyl wettable powder at 1000 times dilution; 50% benomyl wettable powder at 1000 times dilution; 30% triflumizole at 800-1000 times dilution (take personal protective measures); 50% sulfur suspension concentrate (spray at 200-300 times dilution at the first sign of disease, and at 400-500 times dilution when the temperature is above 30°C).
In addition, sodium fluorosulfate is a poison bait, generally used at a concentration of 15%, to control insect pests.