The Garden Corner by Sharon Allen As promised in last month's Garden Corner, dividing perennials is this month's topic.
Division is one of the simplest and most frequently used methods of plant propagation. It is suitable for perennials which have a spreading rootstock and many shoots produced from the base (such as yarrow, ladies mantle, aster, astilbe, campanula, sea holly, day lily, bee balm, painted daisy, pin cusion, hosta, iris, phlox, sedum, lambs ear, meadow rue and bleeding heart).
As well as being a method of propatation, division rejuvenates plants and keeps them vigorous. Young plants as a whole perform much better than old. For example, bergenias need attention every third year at least if they are to flower as they should. Heucheras (such as coral bells) and chrysanthemums turn woody and unproductive unless handled every two or three years.
As a rule of thumb, most plants should be divided when they are dormant. Realistically, it can be done whenever the gardener has the time. To divide a plant, lift it with a garden fork and shake off as much soil as possible. Then wash the crown in a bucket or hose it clean of any residual soil. Shorten any tall stems to prevent unnecessary water loss, especially if the division takes place in summer.
Break off a piece with at least one good "eye" (growth bud) from the periphery of the crown, where the young shoots are generally produced: avoid the central woody crown, which is of no value and should be discarded. If the piece proves difficult to remove, cut it off using a spade or sharp knife.
Some plants with loose crowns (such as asters) are easy to pull apart by hand. Replant divisions as soon as possible. Water newly planted divisions thoroughly; take care not to expose the roots by washing away any soil.
Peonies require special care, because they tend to reestablish slowly after being transplanted.
To learn more about dividing perennials (such as peonies, irises, lilies, and day lilies) attend the free Plant Division Workshop that I will be offering Saturday, Sept. 30 at 10:30 a.m. at my house, 110 North Plum Street, Vermillion. For more details contact the Clay County Extension Office at 605-677-7111.
Written by Sharon Allen, Master Gardener Intern and free lance writer. For answers to gardening problems write to Sharon Allen, care of the Clay County Extension Office, 515 High Street, Vermillion, SD 57069, or contact Allen directly through the Internet at firstname.lastname@example.org.