Redefining the ‘perennial garden’
By Dawn Pettinelli - UConn Home & Garden Education Center
Feature Article - posted Thu., Mar. 24, 2011
Although their name may suggest otherwise, perennial beds and borders do change with time. They need to be reevaluated every few years. Plants may need to be moved to a different location where they will either look or grow better. A great number of perennials will benefit from division. Perhaps those trees nearby have extended their branches enough to alter the amount of sunlight now available. Maybe that cute little 4-inch pot of gooseneck lysimachia you planted had laid claim to more than its fair share of the garden. Or, even your tastes in colors, design ideas or seasons of bloom may have changed. Whatever the reason, spring is a good time to overhaul the perennial garden.
Before you pick up that spade and begin digging, you need to decide on the type of look you are aiming for. Your site conditions will likely dictate your choice of plant material. Try as you might, perennials like gaillardia, lavender and dianthus will not do well in soggy soils, while hellebores will wither away in hot, dry exposed sites. Consult one of the many books or websites on perennials, talk to a knowledgeable person at a local garden center, or call the UConn Home & Garden Education Center if you are in doubt about a plant’s cultural requirements.
Another factor to consider is the maintenance many perennials require for their best display. Delphiniums in all but the most sheltered areas need to be staked. Yarrows and evening primroses should be divided every couple of years. Garden phlox must be religiously deadheaded so its usually magenta-colored progeny do not take over the world. Lilies need the once-over just about every day to patrol for lily leaf beetles. And, some plants like columbine, rudbeckia and agastache seem to have relatively short life spans, at least in my yard, and just require regular replacement. I don’t believe a plant exists that does not require at least occasional attention, but if you are limited in the amount of time you have to deadhead, stake, divide and control pests, you will definitely want to choose less demanding perennial species.
When redoing your perennial beds, keep in mind also the season of bloom. Many perennials, for all their loveliness, have a tendency to bloom over a short three- to six-week span of time. A few will provide color, or at least interest from early summer until frost. These include plants like hostas, coral bells, Russian sage, and some dwarf daylily cultivars. Some gardeners strive for a riot of color for mainly one time period – say, the month of June – while others prefer smaller portions of color that extend over the whole growing season. Spring flowering bulbs and annuals can provide interest either by complementing the flowers of perennials or as fillers when little else is blooming.
Spring is generally a great time to divide mid- and late-season flowering perennials, with the early fall being better suited for the early spring bloomers. If you cannot replant the divisions immediately, pot them up, or heel them in somewhere not in full sun. Perennials with a long tap root like baby’s breath and echinops do not appreciate being moved, so place them carefully. If you need to move Oriental poppies, wait until they go dormant, usually in July or August.
Think about what bulbs you might like to see blooming with your early season perennials and make a note to purchase them for fall planting. Place the bulbs behind sprawling perennials so that the dying bulb foliage will be camouflaged. Don’t be afraid to experiment and, most of all, don’t be afraid to rectify any unsatisfactory plantings. Unlike permanent tree and shrub plantings, a perennial garden can be modified to suit your needs and desires.
For information on perennials or on other home or garden related items, call the UConn Home & Garden Education Center (toll-free) at 877-486-6271, visit the website www.ladybug.uconn.edu, or get in touch with your local Cooperative Extension Center.