1、 Excessive watering

1. Reason: Dahlia doesn't like too wet environment. If it is watered too much at ordinary times or drenched with too much rain in the rainy season, the leaves may dry up

2. Measures: in this case, the watering can be suspended for a period of time, or the excess water in the basin can be discharged. When the plants return to normal, continue watering

2、 Fertilizer concentration is too high

1. Reason: if the fertilizer is too thick or applied directly to the taproot, root burning may occur, and then the leaves will dry up

2. Measures: firstly, it is necessary to suspend fertilization to see whether the plant will return to normal. If the situation is serious, you have to take off the pot and trim the roots

3、 Disease causes

1. Reason: there is a special disease, which will lead to the drying of Dahlia leaves, which is called "Dahlia dark streak disease". It is highly infectious and harmful

2. Measures: the dried leaves must be cut off and must be handled properly to expand the scope of prevention and treatment of infection. Then use chlorothalonil once in about ten days. Generally speaking, it can be cured by spraying once or twice