Watering properly is much more an art than a science. When watering turfgrasses, wet the soil to a three to four inch depth. Normally, this should create enough reserve moisture in the soil that you will not need to water again for two to four days depending upon rainfall amounts, if any. It is best to water a lawn heavily and infrequently. One common mistake with irrigation systems is that too much water is applied every day, which can lead to disease problems during the summer.
To determine the soil moisture depth, use a screwdriver or a garden trowel. Push it into the soil and if you meet little resistance, then the soil is wet. If it does not push easily into the soil, then additional water will be needed.
Sandy soils will need to be watered more often than clay soils, but less water is needed to wet a sandy soil to the four inch depth.
Your lawn needs a minimum of 1½ inches (3-4cm) of water weekly.
Regular waterings are better than light sprinkling. Your lawn needs a minimum of 1½ inches (3-4cm) of water weekly depending on soil type, wind and rainfall amounts. This will encourage strong healthy roots. Heavy watering results in waste and promotes lawn problems eg. disease.
Early morning is the best time to water.
Midday watering - during hot, dry weather - can waste water, since much of the water evaporates. Evening watering promotes the spread of disease. Early morning is the best time to water.
The symptoms of drought begin with a dark silvery tinge to the grass blades. At this point your foot prints become clearly visible. If action is not taken to correct the problem, the grass plants will die and turn a straw color.
If lawn shows symptoms of drought, water it immediately regardless of time of day.
An easy way to water hills is to use a soaker hose with the water holes turned down towards the ground. Flood the hill until puddles appear at the bottom. Ask your local Weed Man for watering recommendations.