I am sorry for this delayed reply to your gardening question. The spring rush has brought a deluge of questions and we are working hard to catch up!
Great question! There are a lot of old adages in gardening that are not true or perhaps are true in one area or situation but not another. This one about the time of day when you water is partially true. Here's the facts. Plant diseases are promoted by wet conditions. Whenever water sits on a plant surface for a given period of time within a given temperature range certain diseases are able to infect the plant. When you water early in the morning less water is lost to evaporation during the watering cycle and the plant surfaces tend to dry out faster with the rising sun and often and increase in breezes. Watering at night means the plant stays wet for much longer. This increases the chances of plant diseases in general. Root rots are most commonly brought on by overwatering or creating soggy wet, poorly aerated conditions around the roots.
Watering once or twice at night is not going to cause disease to break out all over the lawn and landscape. But doing this as an ongoing habit can result in more disease problems. Extended rainy spells also result in an increase in diseases. We can't control the rain but we can keep from adding insult to injury by over watering and watering at the less desirable time of day, namely the night time hours.
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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