This batch of Ficus umbellata has been potted up from plugs for about two months. In the first few weeks, only about 20 pots of them showed signs of leaf spots. After two months, almost the entire batch had the same condition.
Plant disease develops when environmental conditions favor bacterial growth. Leaf spot is one of the major symptoms that are caused by bacteria, and mostly appeared under the conditions of high humidity and low temperature.
We shall respond quickly when plant disease symptoms appear to stop the spread of the larger infection. Prepare the wettable powder containing Mancozeb 80% and Chlorothalonil 75%, 50 grams of each, and mix with 50 liters of clean water for making the pesticide. To ensure the solution of pesticide is smooth enough to avoid remaining residual pesticide on leaves, adding an appropriate agr engine is necessary. We suggest applying the pesticide once a week. Also keep in mind to keep the greenhouses ventilated, rise the light intensity, and lower the humidity to make sure the roots are unrotten. Sick leaves will be gradually defoliated while new ones keep shooting up when the weather becomes better.
They can still be treated even when the bacterial infection spreads. We should pay more attention to caring for them and keep them away from groups of healthy plants. Prepare a pesticide with 100ml of Propamocarb Hydrochloride and 50ml of Hymexazol 30% soluble solutions in 100 liters of water, applying it once a week. As we mentioned above, be noticed about environmental factors ensure the safety of roots.