Recent wet winter weather reminds us of why good drainage is
important for healthy
perennial beds.

“As long as the water is moving off of the bed, you don’t have
problems with wet
weather,” said Gary Wade, a University of Georgia Extension
Service horticulturist.
“When the water is standing in the bed, you have big
problems.”

To avoid those critical pockets of standing water, start with a
good drainage system.

“If you have water problems now, there isn’t much you can do,
short of ripping out your
perennials and starting over,” Wade said. “You have to create a
good drainage system
from the beginning.”

He recommends tilling as deeply as possible to break up any
hardpan that lays beneath
your beds.

“You can also raise beds four to six inches above the grade,” he
said. That will not only
allow the bed to drain better but will help people see the color
display better, too.

If you don’t know if your bed has poor drainage, try a simple
perk test.

“Just dig a hole in the bed and fill it with water,” Wade
said. “Come back 24 hours later,
and if the hole still has water in it, you have poorly drained
soil.”

If you have bad drainage, about the only relief you can offer
your beds is to carry the
water off the site.

Wade warns against adding sand to Georgia’s clay-laden soils in
an attempt to increase
drainage. “You can create cement,” he said. “That would be
detrimental.”

Instead, Wade recommends bringing in good topsoil.

While Georgia seems to have had an abundance of rain this
winter, he said, it’s actually
normal February weather.

“We have to remember that most perennials have very shallow,
fibrous root systems,” he
said. “So those that are hurting now are those in badly drained
beds that allow water to
stand and suffocate the root systems.”

Wade said some perennials such as Siberian and Japanese iris,
hosta, liatris, lobelia, astilbe,
phlox, monarda and physostegia are very tolerant of moist sites
and can survive wet
periods without a scratch. Yellow flag iris, he said, will grow
in standing water and is
often used in pondscapes.

Some homeowners try to help their beds’ drainage by removing
their mulch.

“That does more harm than good,” Wade said. “If you remove the
mulch, you’re exposing
the roots. When we get a few sunny days, the roots will be
damaged by the drying effect
of the sun. Just leave your mulch in place and cross your
fingers that we don’t get much
more rain.”