During drought conditions, lawns should be watered regularly or allowed to go dormant. Irregular irrigation that caused lawns to repeatedly enter into and recover from dormancy can severely weaken them. How you water your plants can drastically affect the efficiency of water usage as well as the ability of plants to survive. Watering once a week causes lawns to become weakened as turf plants repeatedly enter into and break out of dormancy. The best time to water is the early morning.
Evening watering leaves turf plants damp most of the night and allows diseases to attack.
During the drought of 1988, many lawns that received continuous night watering succumbed to fungal diseases. Water lawns so that moisture penetrates at least a couple of inches. Deep, less frequent watering promotes deep root structures and so improves drought resistance. Shrubs Lawn sprinklers generally should not be used to water shrubs. Contrary to popular belief, wetting the leaves and stems increases the humidity only for several minutes.