Q: I have heard two trains of thought regarding summer watering. 1. Watering in the morning causes problems because moisture on plant leaves could burn them when they are in full sunshine. 2. Watering plants in the evening creates fungus problems if too much moisture sits on the leaves at night. Which is correct?
A: The first train of thought is headed down the wrong track. Despite tales from supposed garden experts, moisture on the leaves does not cause leaf burning. Ask a high school science student to explain it to you by studying the focal points of curved lenses.
The second train of thought, though, is exactly correct. Most foliar diseases need twelve to fourteen hours on a wet leaf in order to cause trouble. If you water at 6:00 p.m. after work, leaves stay wet until mid-morning the next day. That’s plenty of time for “fun guy” fungi to have a party on your lawn or landscape plants.
The best time to water is anytime after midnight until 10:00 a.m.. Be sure to follow the current local and state watering restrictions.