Friday, May 23, 2003
Unchecked sprinkler systems are the biggest cause of root rot, says one expert.
KNIGHT RIDDER NEWSPAPERS
COLUMBUS, Ga. -- If plants could talk, diagnosing their ailments would be a lot easier. "Keep Rufus from stomping a trail through me," the ivy might say. Or, "I could use some slug bait over here," the hostas would complain.
More than likely, though, all plants would be screaming, "Throw me a life preserver!"
It's a common tale that plants die every year by drowning -- and not because they fell into the swimming pool.
When perennials appear wilted and shrub branches start dying, a homeowner's first inclination is to pull out the ol' water hose and soak them again.
"It's sort of a vicious cycle," said Karl Pearson, extension agent for the Muscogee County (Ga.) Extension Service. "Plants look droopy so people think, 'Hey it needs water,' and they keep pouring it on until they drown it."
According to Pearson, the biggest cause of overwatering -- and consequently root rot -- stems from automatic sprinkler systems.
"People try to water their lawn and plants at the same time," Pearson said. But turf grass needs more water than your average plant. While turf grass is happy being watered every other day, established shrubs and perennials need water once every two weeks. Some only need it once a month, if it rains.
Plant placement
Gill Cargill, owner of Gill Cargill Landscapes, said it's important to consider plant placement when installing a sprinkler system.
"You want to make sure they aren't planted too close to a sprinkler head," he said, so plants don't get soaked.
But it's also important to use a sprinkler system properly.
When Cargill installs a new sprinkler he advises homeowners to use it as needed, rather than setting it on an automatic timer.
"People should wait for grass to show signs of stress," or turn a bluish-gray cast, he said.
"You don't want to wait to the point of damage," but it won't hurt grass to let it dry out between waterings, Cargill said.
And if you're lucky, mother nature will take care of some waterings.
If it rains, common sense should tell you not to turn on the sprinkler, Pearson said. And if you're unsure of whether your plants need water, the best indication is to check the soil.
"Go out there, pull back the mulch and feel the soil," Pearson said. "If your plant is standing in water, it probably doesn't need any more."
Slow soaks
Plants need to establish a deep root system in order to sustain themselves during drought seasons. Therefore, how much you water a plant is just as important as how often you water it.
Long, slow soaks are more effective than shallow sprinkles.
Pearson said plants should be soaked to an 8-inch depth. This can be done by timing the volume of water your sprinkler sprays in an hour.
"Take a shovel and dig up a chunk of soil to see how far down the water soaked," Pearson said.
Container plants should be flooded until water seeps out of the drainage hole.
"This also helps leech out any salts that are in the soil," said Frank Bennett, owner of Columbus Flower Market. But make sure to empty the clay saucer.
"You don't want the pot to be sitting in a pool of water," Bennett said.
And you may need to stagger water times if your yard has clay soil or poor drainage.
"Sometimes the water will just run off rather than soaking in," Cargill said.
Automatic sprinklers can be set for 20 minutes twice a day rather than for a one-hour dousing. A good schedule would be 4 a.m. and no later than 4 p.m.
"You want plants to have time to dry out before it gets dark," Cargill said. Otherwise, mildew can set in and cause plants a different kind of woe.