Watering Constantly

Since last Tuesday, when the temp. hit 24 degrees Celsius, I have been watering daily. My bonsai soil dries out enough to water daily. These trees I will have to move into more shade as the seasons pass. The plants in nursery soil have to be watered daily even though they are not dry. If they are not watered daily when warm, it is difficult to re-wet them. Watering them so much causes worts and mushrooms to grow - because of warm, wet soil. Guess what else grows well? Bacteria and molds which kill trees. But it is that or a sure death with dehydration.