GARDENER'S READING ROOM
Perennials

Perennial Perfection: Dividing Your Dazzlers

Are your beloved perennials trying to tell you something? Are you seeing weak leaf and flower displays, or gargantuan growing greenery?

Many perennials exhibit signs that they need to be divided. For example, growth can be lackluster with weak leaves and small, infrequent blooms. Also, the centers of perennials clumps may become hollow and woody. In some cases, your plants are growing too big for their allotted space. Or you may simply wish to share some of your crowded collection with a friend. Whichever the case, some simple guidelines will help keep your beauties the picture of health.

Most perennials should be divided every two to three years. As a general rule, dig and divide spring or early-blooming perennials in the fall and late-blooming perennials in the spring. For example, Bearded Iris is a spring bloomer, so divide in July to late August. Chrysanthemums, on the other hand, bloom later in the season, and should be divided in early spring. This difference in division time allows optimal root and leaf growth in order to prepare for a successful season of flowering.

There are perennials that you should not divide. Peonies, Hellebores, and Lupines prefer not to be disturbed and will remain tidy and beautifully blooming for many years. Lavender, Russian Sage and Euphorbia are more like small shrubs. When these become too woody, hollow, or overgrown, the best option is to rip them out and start over with a younger plant. There is an expiration date for perennials!

Beware! Avoid dividing a plant when it is in flower. In most cases, the flowers will drop and the plant will not bloom again until the next season. It is also best to refrain from dividing during the heat of the summer. During the spring and fall, we have rains that provide a nice source of water to keep our new divisions well hydrated. You should be done dividing and transplanting perennials by mid-September. Anything divided and planted later may not have enough time to ready itself for the frosts of the winter.

Perennials are the spectacles of our spring and summer gardens, the fireworks that dazzle and amaze. The promise of their flamboyant displays gives many of us hope during the long and wet winter months. Dividing clumps of perennials at the correct time in the plant’s lifespan ensures robust growth and hardiness, keeps size in check, and multiplies the number of dazzling floral displays. So get out in the garden and listen to what your perennials are telling you!

By Meagan McManus
Skylights Autumn 2006, Vol 21, No. 3

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