Wasting Water By Saving It
The Los Angeles Times tells us water demand in Los Angeles has reached a 32 year low due to new water restrictions in place there. I don't know that demand is the right word to use in this situation, is it? Maybe water use per household is at a 32 year low? After all, if they have to restrict water use then the demand for it is still there.
But, that's a good thing, except I don't understand their lawn irrigation restrictions. Sprinklers are only allowed to be used for 15 minutes, 2 days a week. I don't know much about the requirements of warm season grasses that make up the bulk of lawns in Southern California, but I can't imagine a half hours worth of water a week would be enough to keep lawns green. Nor would the 45 minutes also proposed.
I know cool season grasses up here need at least an inch of water a week to stay green and growing. I'm sure it's the same down there. If they're going to restrict watering to a half hour to 45 minutes a week, they might as well just restrict lawn watering altogether since any water used is being wasted since it's not accomplishing its purpose.
The same goes up here. It takes hours to put an inch of water on a lawn, depending on the flow of your irrigation system. If you just run your sprinklers a half hour a week and the lawn stays brown and dormant, why keep wasting water? Just wait until the rains come for your lawn to green again.
For those of you keep- up- with- the- Joneses types that want the greenest lawn in the neighborhood, the way to figure out how long it takes to put an inch of water on your lawn: Get some coffee cans or other straight sided containers. Place them randomly around your lawn to get a good average measurement. Turn on the sprinklers and see how long it takes all of them to get an inch of water. That's the minimum you should be watering and it's best to water once a week since deep watering encourages deep root growth.
As far as the time of day: I see both Sacramento and Los Angeles don't allow watering during the heat of day, which is good. But the best time is probably at night as there's less wind and less evaporation at night.
Just make sure to turn the sprinklers on during the day every now and then to make sure they're working right. You don't want to be like the fellow up the street a few years ago who was missing a sprinkler head and the water was running straight into the gutter. Don't know how many gallons he wasted until he took care of the problem.