By Laura Pottorff, Colorado State University Cooperative Extension agent, horticulture and plant pathology
If you are looking for a flower garden that will be a long-term investment in your home landscape, you'll want to consider planting perennials -- flowering plants that bloom year after year.
Unlike annuals -- the bedding plants that you will begin to see from now on in garden centers and other stores -- perennials do not die out each winter. They last through the year and send out new and stronger stalks and foliage each spring.
In most cases, it's easy to tell the difference between annuals and perennials, but not always. So the first thing you'll need to do is be sure of what you are buying. Cost is one clue. The initial cost is greater for perennials, but the plants are a permanent addition to the garden. In the long run, they may be less expensive than buying annuals each year.
You can plant tall perennials at the back of a border and shorter plants in front. With a little planning, it is possible to plant masses of successively blooming flowers for an all-season display. After three years, most perennials need dividing, giving you and your friends hundreds of new plants.
Here are some planting hints for perennials.
Established perennials may need to be divided every three or four years to maintain vigor. Perennials that bloom in the spring and early summer (peonies and poppies) usually are divided in the fall or when foliage dies. Medium to late summer and fall flowering types (chrysanthemum and aster) should be divided in early spring before growth begins. Iris and day lilies usually are divided immediately after flowering.
Photograph courtesy of Judy Sedbrook.
© CSU/Denver County Extension Master Gardener 2010
888 E. Iliff Avenue, Denver, CO 80210
Date last revised: 01/05/2010