Without an irrigation system to measure the amount of water applied to your landscape, you may be wondering how long to leave the sprinkler on. Generally, the recommendation is to apply 1” of water twice a week less the rainfall.
To measure, place a cup in the area to be watered and time how long it takes to get 1” of water in the cup. Once you know how long it takes, to apply 1” of water, you know how long to leave the water running.
For soaker hoses, turn the water on no more than half way for several hours or overnight.