How to deal with the yellowing of flower leaves

The reasons for the yellowing of flower leaves are different, and the methods of treatment are also different. Caused by improper watering, need to control water, only need to keep the soil moist, but can not leave stagnant water, nor too little watering, will lead to soil hardening; caused by light, need to move to the astigmatism for breeding, and spray some water to the leaves; due to the small amount of fertilizer, it is necessary to apply fertilizer in time, but not too much at one time, so as not to cause root burning.