May/ June 2002 Excerpt

Excerpt from Architectural Annuals


Plants with proud bearings, majestic profiles, and shapely silhouettes accommodate a variety of landscaping needs—and all in a very short time. 
by Rita Pelczar

“Instant gratification” and “gardening” are words not often used in the same sentence. Gardening, by its very nature, is a process that involves time—often years—to achieve desired effects. Perennials and ground covers need to spread to fill their allotted spaces, and trees and shrubs must gain size to develop their characteristic form and to reconfigure the horizon.

Annuals accelerate the process. Though their effects are not exactly instantaneous, they grow at warp speed compared to most woody plants, allowing gardeners to effect lively changes in the landscape in a very short time. Certain annuals—those big, fast-growing types with bold silhouettes or towering habits—can provide dynamic results in mere weeks. They allow you to fast-forward a design, testing plant sizes and forms for your garden spaces before you go to the expense and effort of a more permanent planting.

Because they are annuals—for our purposes we include both true annuals and tender perennials grown as annuals—the effect is fleeting; a repeat performance will require replanting next year. But the ephemeral nature of annuals has the built-in advantage of great flexibility.

In an architectural sense, large annuals can fulfill many roles. Some create drama as an accent in a mixed bed or alone as a specimen. Others grow quickly to form a dense hedge that screens a view or encloses a space.

Characteristics that should be considered in selecting the best annual for a specific placement and purpose include overall size (both height and spread); form (rounded, angular, erect); color (flowers and foliage) and mass (open or dense). And, of course, the cultural preferences of a particular plant must fit the site. 
You say you’re considering putting in a hedge along the back fence but can’t quite envision the look from your deck? 

Try a densely planted, double row of spider flower (Cleome hassleriana). You will have a three-to-four-foot hedge in a few weeks, not to mention flowers that will bloom from summer until frost. If the hedge look seems to work, you can plant something more permanent later. Another colorful option for an annual hedge is love-lies-bleeding (Amaranthus caudatus), a bushy plant that reaches three to five feet tall and produces drooping, red tassellike flowers from summer through fall. Or you could try the Mexican sunflower (Tithonia rotundifolia) with its dark green leaves that set off the fiery orange flowers to perfection. 

This dependable performer even grows well in poor soil. Another option is summer cypress (Bassia scoparia forma trichophylla, formerly Kochia trichophylla) which rapidly grows to five feet tall and tolerates shearing. Though its flowers are insignificant, it produces feathery, bright green foliage that turns red in the fall.

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