Why is it a good idea not to water in the hottest hours of the day? Water can evaporate before it ever hits the ground from hot, midday temperatures and strong winds leaving only a little water to soak deep down where plant roots should be growing. To meet the plant’s needs, water should be applied to the soil slowly so that it can soak in deeply. This encourages deeper, wider, more extensive roots well below the hot surface soil. Because of these benefits, the City of Gallup has Time and Day of Irrigation (PDF) regulations. Another advantage of watering early in the morning or late evening, is that plants stay healthy while you conserve our most vital resource - water.