Despite an ongoing love affair with hardy perennials, many Minnesotans are taking a second look at adding old-fashioned flowering annuals to their gardens. These once-again-popular plants provide a link to the simplicity and charm of gardens past. And what's more, many of them also have fragrance, something that's often missing in newer, highly bred cultivars.
Because most people live in homes on relatively small lots and garden in modestly-sized spaces, plant breeders have emphasized the development of shorter, more compact versions of many old-fashioned annuals. In some cases they've come up with larger flowers -- zinnias and marigolds, for instance -- on shorter, smaller plants. The net result is more color per square foot, but the new plants may lack the grace and the fragrance of their predecessors.
Don't get me wrong; plant breeders generally deliver annuals that are superior in many respects. For example, a new variety might be more disease-resistant, flower abundantly without the need for dead-heading, or bloom consistently until killing frost. Their flowers might be a brand-new color or an improved form (doubles, for instance). And sometimes just the compact form is an improvement because it's less likely to topple after a heavy storm.
All the same, there's something particularly appealing about growing the same plants our great-grandmothers grew. Here are a few old-fashioned favorites that are making a comeback. (You should be able to find most of these plants at garden centers, either as small plants or in seed packets.)
'Blue Horizons' is an ageratum that can grow to a height of 2Â½ feet or more, which is quite a contrast from the compact modern ageratum commonly sold as edging plants. 'Blue Horizons' has long-lasting, sky-blue blossoms that are attractive when massed in a garden, but also make excellent cut flowers.
While newer cultivars are only a foot tall, the older bachelor's buttons such as 'Blue Boy' grow to nearly 3 feet. Like tall ageratum, they are lovely in bouquets. Seed bachelor's buttons directly into the garden once frost danger has passed. (They're fun for children to plant because the seeds look like little shaving brushes.)
Flowering tobacco (Nicotiana sylvestris) fell out of favor because of its tall stature -- it often grew 4 to 6 feet tall. But this flowering tobacco is enjoying renewed popularity because of its fabulous fragrance, which perfumes the night air. It has slender, tubular, cream-colored flowers that hang from a central stalk, which grows taller as more blossoms develop.
Before we had the wide array of impatiens currently available, garden balsam (Impatiens balsamina) was popular with gardeners who wanted to add color to shady gardens. These plants grow about 2 feet tall, producing flowers all along their upright stems. The double blooms come in lovely pastel colors, but are unfortunately partially hidden by the leaves. While the newer impatiens are showier, these are fun to grow for the novelty.
Heliotrope are prized for their delightful fragrance. To take advantage of their vanilla-like scent, add heliotrope to large container gardens by your front door, deck or balcony. That way you can enjoy them every time you pass by. Heliotrope's large clusters of tiny purple flowers look good massed together in a ground bed too. Keep in mind that they need plenty of water.
The combination of beautiful blossoms and honey-like fragrance are enough to entice gardeners to try sweet peas, despite the fact that the plants may deteriorate as we move into summer. Because they prefer cool growing conditions, sweet peas perform better some years than others. Look for heat-resistant cultivars and seed them immediately along a fence or trellis where they get morning sun.
A couple of oddballs
Love-lies-bleeding (Amaranthus caudatus) and Kiss-me-over-the-garden-gate (Persicaria orientale) have large leaves and pendulous "tassels" of flowers. Love-lies-bleeding grows about 3 or 4 feet tall, producing drooping red tassels (the "blood") that may be 8 to 10 inches long. Kiss-me-over-the-garden-gate is a giant that grows as tall as 5 or 6 feet, then arches over, its rosy pink flower tassels 4 to 5 inches long. Each of these unusual plants can be a real show-stopper in the garden.
Deb Brown is a horticulturist with the University of Minnesota Extension Service Yard and Garden Line. For help with garden, plant and insect questions, call the Yard and Garden Line at 612-624-4771.