Ending just before dawn.

Why? If you water during the day, more water is lost to evaporation before
it even hits the grass. If you water after sunset, some moisture remains on
the blades for too long, and you could encourage fungal problems.

That leaves just before dawn. Less water evaporates as part of the
sprinkling process, and water that makes it to the blades, but doesn't make
it to the soil can evaporate quickly, and not provide a place for fungus to
multiply.

--
Warren H.

==========
Disclaimer: My views reflect those of myself, and not my
employer, my friends, nor (as she often tells me) my wife.
Any resemblance to the views of anybody living or dead is
coincidental. No animals were hurt in the writing of this
response -- unless you count my dog who desperately wants
to go outside now.
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