It is very easy for water to run down the slope without penetrating the soil. Water must be applied at very slow rates. Ideally a lawn should be watered just as it begins to wilt. Most grasses take on a dull, dark blue appearance and the blades begin to roll. You may see foot pints left as you walk over the lawn.
Early morning is the best time to water.
The wind is usually calm and the temperature is low so less water is lost to evaporation. The poorest time to water is in the evening because the blades stay wet longer and the lawn is more susceptible to disease. If water applications are too light and too frequent turf tends to become weak and shallow rooted. This may also cause a heavy thatch development. The result is a turf that is heat, drought, and disease susceptible because it is stressed.