From strictly the standpoint of what is good for the turfgrass plant, water should be applied during the day, preferably during the morning. Doing so reduces the amount of time leaf blades remain wet which reduces disease incidence. While some water can be applied during the day without too much inconvenience to golfers, it is impractical to water the entire course during play. From a water conservation standpoint, the most efficient use of water occurs at night or early morning when it is generally cooler, less windy and humidity is higher so evaporation losses are less. Well-designed irrigation systems make is possible to precisely apply water at night which can have the added advantage of capitalizing on lower energy rates charged at night, which saves the golf facility money and makes your round of golf more affordable.