The next few weeks will be the ideal time to plant new
perennials or divide and relocate
established perennials in Georgia.
By allowing the plant to reestablish its root system during
October, November and
December, perennials are then well-prepared to endure our
winters. A well-established
root system will support rapid growth and optimal flowering the
following spring.
There are several reasons to relocate or at least divide and
replant perennials. The main
reason is that many, if not most, perennials grow into large
clumps or colonies.
Competition for nutrients, water and root space tends to reduce
the vigor of the entire
group.
Irises, hostas, phlox, liatrises and shasta daisies, for
example, will remain vigorous if
divided about every three years.
There is another reason replanting perennials is a good idea.
Whether you live on
piedmont clay or sandy soils, rainfall, garden foot traffic and
gravity slowly compact the
soils.
Annual beds, dug every spring, tend to have good porosity and
air movement in the soil.
Perennial beds, though, are usually left alone and need
attention about every three years.
Before you do anything, take a soil test to the county Extension
Service office. When you
get back the lab’s recommendations for amendment and nutrition,
then start digging.
You can use a shovel to divide really tough perennials such as
red hot poker, day lily,
phlox and swamp sunflower. My experience with perennials,
however, leads me to suggest
you divide plants such as hosta, iris, coneflower, shasta daisy
and other more fragile,
clump-forming perennials by hand.
Dig up the clump at the edge of the dense root system, knock off
the soil carefully and
then feel through the root system for natural clusters or points
of separation. Each
perennial is different, but with a little feeling around, it’s
usually easy to do.
Pulling the clumps apart gently, with increasing force, will
give you an idea if they come
apart naturally or if you will need a hand pruner to cut
connecting roots. My philosophy is
that the fewer roots you cut, rip or tear, the less likely
disease will get a foothold.
I like to let fleshy roots, tubers and corms dry out for a day
before transplanting. I replant
and water-in soft fibrous roots as soon as the bed is prepared.
Be sure to pile up divided
perennials out of direct sunlight.
Preparing the bed is simple. Add the recommended amendment, then
till or dig to at least
12 inches deep. Add only a very little nitrogen to the soil so
as not to push new growth
easily killed by frost.
Your perennial bed soil may look mounded by 4-5 inches when you
finish. This is a good
sign you have done a good job. Rake the soil evenly into a
smooth, slightly sloped mound.
Plant your perennials in the soft soil. Do all you can to avoid
compact the soil with your
knees and feet. I do this with a 3-inch-thick pile of newspapers
to kneel on. Or I use a
piece of plywood as a plank.
Once the planting is done, irrigate the entire bed with a
sprinkler for two to three hours.
The bed will settle some. Don’t worry. The bumpy look will
vanish by March.
After watering, cover the bed with 3 inches of pine straw to
reduce erosion and rain
compaction and to keep the soil cool. This will also prevent
early warmup and premature
growth.
Be sure to add 10-10-10 or a similar fertilizer in late spring
when the new plants start
growing. Remember, too, to check the moisture in the newly dug
bed. If we have a dry
spell in October, you may need to water.
