Summer in Georgia means sweltering heat and widely scattered
showers and thunderstorms.
Your neighbor could get an inch of rain in their yard, while
yours stays bone dry.

"These isolated showers are usually just not enough to
keep a yard green,"
said Kerry Harrison, an engineer with the University of Georgia
Extension Service.
"Most turfs need an inch to an inch and a half of water
every week."

A notable lack of rain lately has had many Georgians dashing
to water hoses. But do
your homework first. Timing is everything, Harrison said.

When watering lawns, the only water that matters is what
makes it to the roots.
Applying too little or too much at the wrong time may hurt your
lawn while raising the
water bill.

So it’s
crucial to know how much water gets to the grass roots, Harrison
said.

"Not knowing your irrigation’s rate of application,
whether it’s a sprinkler on a hose or a
permanent system, is like driving a car with no
speedometer," Harrison said.

Different systems apply water at different rates. Of all of
the systems available,
sprinkler hose combinations have the most variance in rate and
the least uniformity. Use
several rain gauges spaced evenly in the watering area to learn
your system’s application
rate.

No matter what your application rate, when you water affects
how much actually reaches
the grass roots, where it’s needed.

"We have research, numbers and all the evidence we need
to know that you can lose
as much as half the water if it’s put out during daylight,"
Harrison said.

Direct sunlight, high temperatures and a light wind can
evaporate or blow water away
from both the water stream and from the ground.

"That means you have to put out twice as much," he
said. "And your water
bill may be twice as high. But your grass won’t benefit an equal
amount."

When should you water your lawn?

Nighttime is best, Harrison said.

"It’s
better for the grass, it’s a better use of the water and it’s
usually easier to get
better water pressure," he said. "The only way it’s
not better is for the
person who might have to get up from bed to turn it on or
off."

A timer, though, can do that for you.

Many permanent systems are on timers. It’s usually fairly
easy to change that timing to twice a week, watering
each time enough to apply about three-quarters of an inch. Many
garden centers carry
timers that work just as easily on hose faucets.

Watering during the day increases the time the grass is wet
and makes disease problems
more likely. At night, the grass is wet from dew already, so
more water won’t hurt.

Applying a little water often will keep grass roots close to
the soil surface. So they
don’t reach the
nutrients and water that are available deeper. A thorough
soaking once or twice weekly
helps roots grow deeper, resulting in healthier grass.

Watering twice a week allows another chance for rain to
supply the other half of the
water needed each week, Harrison said.