Divide and Conquer: Preparing Spring Plants
FOR IMMEDIATE RELEASE
April 1, 2014
URBANA, Ill. - Spring is here and we are starting to get the
gardening itch, said a University of Illinois Extension horticulture
"Warm days tease us and blooming crocus encourages us," said
Martha Smith. "But we know Mother Nature is still in charge and she can release
her fury at any time. Now is the time to start thinking about what will need to
be divided in our gardens.
"In general, most perennials need to be divided every three
to five years. The ideal time is in the spring just as active growth starts. It
is at this time you can do the least amount of irreparable damage. All systems
are go! The plants are coming out of their dormancy and are primed for
growing," she said.
Some may argue that there are specific plants that respond
to dividing better at later times during the growing season. "Yes, that is
true. The recommended time for oriental poppy, peony, and Siberian iris is late
July or early August, but spring is still okay if that is the only time you can
divide," Smith said.
Divide early spring bloomers after bloom and they will have
all season to anchor new roots and set buds for next spring. Divide summer-fall
bloomers in spring and they too will be able to set roots and respond to
daylight and temperatures to bud and flower. For the majority of perennials in
the garden spring is a great time for dividing
Usually a plant will show signs of needing division. They
become overgrown with dead, unsightly centers, or their vigorous growth has
sent them to places in your garden where they are not welcome! Plants often
have fewer or smaller flowers and are in overall poor health due to the plant
depleting the fertility of the soil as it crowds itself.
"Let the plant be the gauge and not a calendar," Smith said.
"Some perennials may need dividing every two years while others may not need
any attention for seven years."
To divide mature clumps of perennials, lift the clump and
separate the outer active growing portion from the center. Discard the center
and replant the active growth areas. Be careful not to over-divide. Leave a
proportionate amount of roots to crown. Too few roots will not be able to
support a large crown. Too small a crown will not give you much of a visual
display. Too large a clump may mean you'll be dividing this plant again
"Don't worry about being rough," she said. "Some perennials
need a backhoe and a pickaxe! After lifting these brutes, use a saw or a sharp
flat-edged shovel. On the softer side, some perennials lift very easily and you
can actually separate them with your hands."
Replant the portion you are keeping and discard or give away
the rest. Prepare the planting area by adding compost or aged manure. Remember,
a perennial can be expected to live in that spot for several years so take a
few minutes and amend the planting area. You will be glad you did.
"You should stagger your plant divisions so that the whole
garden will not need dividing at the same time," she said. "A good three-to
four-year-rotation plan will yield a nice display of flowers each year. "
Source: Martha A. Smith, Extension Educator, Horticulture, email@example.com