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How to Water One Inch a Week

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Did you know your lawn only needs one inch of water a week - this includes rainfall!

How do you know when you have watered 1 inch?
Here is a simple way to figure out how long to water your lawn:

Set out 5 tuna cans (or something similar) at various places on your lawn within your sprinkler�s range. Place cans halfway between the sprinkler and in the areas that generally receive the least amount of sprinkler water.
Turn on your sprinklers for exactly 15 minutes.
Measure the depth of the water in each can. Add the numbers and divide by 5 to get the average water depth (in inches) of all the cans.
Check the following chart and locate your average water depth. The box to the right of that number lists your total weekly watering time.

Average Depth in the Cans (in inches) After 15 Minutes	Number of Minutes to Water 1"
1/8	120
3/16	80
1/4	60
5/16	46
3/8	40
1/2	30
5/8	24
3/4	20
1	15
1-1/4	12

Watering at the best time
Heat and wind cause water to evaporate more quickly. By watering early in the morning, when the air is calm, evaporation is kept to a minimum, and results are the best. Watering in the evening is next best.

Getting rid of puddles and runoff
If water puddles or runs off to another part of the landscape, the soil may have a high clay content. Reduce watering time to avoid runoff.

In any case, watering for shorter periods over a longer total time will give the best results. Consider installing a timer at the outdoor faucet to make this an easier job.

If there are still problems getting water to penetrate the soil, the lawn may need to be aerated or thatched. Yard and garden centers in many areas carry the right tools for this job, as do many equipment rental companies.