Lucky: Look, teacher, what's wrong with this? When you touch leaves, they will fall off.
Memories of late summer: black spot disease, I told you last time, the diseased leaves were picked. In this season, the temperature difference between day and night is large, and the temperature is gradually decreasing. After dormancy, the nutrition of the rose begins to flow back to the root system, and it is normal to drop it when touched.
Lucky: OK, thanks. I probably didn't notice it last time. I don't need medication.
Memories of late summer: the plants planted can be sprayed with a mixture of stone and sulfur to prepare for winter.
Lucky: OK, I'll buy it right away.
Thanks for the conversation with memory, luck and other flower friends at the end of summer.
Treatment and prevention of black spot disease
1, and select excellent disease-resistant varieties. In the early stage of the disease, the diseased branches can be cut off, disinfected and the plants moved to a ventilated place for maintenance.
2. Fertilize scientifically, increase the application of phosphorus and potassium fertilizer, and improve the disease resistance of plants.
3. Remove the litter after autumn and burn it in time.
4, strengthen cultivation management, reasonable close planting, pay attention to plastic pruning, ventilation and light transmission.
5, timely irrigation, drainage in time after the rain, to prevent water retention.
6. When the new leaves unfold, spray 4% flusilazole or 20% flusilazole prochloraz 800 ~ 1000 times, or 75% chlorothalonil 500 times, or 80% zineb 500 times, 1 0 times, and spray 3 ~.
7. When the condition is serious, black spots will also appear on the stem. At this time, it is best to cut again to avoid the spread of pathogenic bacteria.