Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: THURSDAY, March 15, 1990< TAG: 9104050070
SECTION: LAWN & GARDEN PAGE: 14 EDITION: EVENING
SOURCE: Dr. Robert E. Lyons / Special To The Roanoke Times & World News
DATELINE: LENGTH: Long
Traditionally, the predominant basis for herbaceous plant selection has been only the ornamental value of flowers. However, many prennials have limited blooming periods, thereby emphasizing the importance of foliage as well.
And given the diversity of perennial-plant characteristics, tremendous potential exists for incorporating new textures into a garden. In fact, outstanding leaves or growth habits can be the sole reasons for choosing some species in the first place. The following is a sampling of plants that contribute interesting textures with either floral or foliage characteristics or both.
\ Light textures
\ Many species offer fine or light textures with thin stems, small flowers or highly dissected leaves. Such plants generally don't screen out light entirely or obscure views.
Gypsophilia paniculata (baby's breath) is an excellent selection to create this effect. A multitude of delicate white or pink flowers are produced on tall, wiry stems rising from a basal cluster of gray-green foliage.
Although shorter cultivars exist, the 2-to-4 foot height for most has made them favorite background plantings for shorter, more colorful plants. Baby's breath accomplishes much the same effect in the natural arrangement of gardens as it does in bouquets.
Baby's breath should be planted in bright locations that don't experience drought. Popular cultivars include the double whites Plena and Bristol Fairy, the double pink Flamingo and the shorter (18 inches) double pink Pink Star.
Another herbaceous perennial with fine texture is Astilbe x Arendsii (astilbe). Its feathery plumes of red, white or pink flowers are welcome additions to shaded gardens. People often consider shady areas the most difficult of all garden sites in which to establish colorful displays.
Astilbe's highly divided foliage emerges in spring with an appealing coppery tint, intensifying to green in summer and turning bronze-yellow during autumn. Moist, organic soil is the key to successful astilbe cultivation. Although this prennial prefers shady places, it will perform well in sunny spots that are mulched and adequately watered. A red cultivar that has become very popular is Red Sentinel. The white Deutschland also is growing in popularity.
Finally, landscape designers should not overlook ferns. As a group, they offer probably the widest variety of foliage shapes and textures of any landscape plant. Ferns are invaluable to garden design. They never flower, but chances are the flowers never will be missed.
Places with deep shade and constant moisture provide good settings for Adiantum pedatum (maidenhair fern). Its scallop-shaped leaflets, as thin as tracing paper, are attached to stems like black wires. The shaded fronds respond to the slightest breeze, creating brief movements among landscape plantings that people often perceive as motionless.
It is an unfortunate misconception that ferns are intolerant of sun; many grow beautifully in partial and even full sun. An exceptional choice in this regard is Polystichum acrostichoikes (Christmas fern). This fern adapts well to almost any situation.
\ Bold textures
\ Some landscape sites require bold, impressive textures. This is often the case when a site needs a focal point. Plants that work well in such a situation should have large or broad leaves, tall statures, striking flowers and exceptional foliage or flower colors. They should also provide solid coverage.
Hibiscus Moscheutos (rose mallow) is a good example of a plant that provides strong texture to landscapes. Not only does the plant grow to an impressive height of 6 feet, but it also has flowers that often measure from 6 to 12 inches in diameter. Petal colors range from deep red to pure white. Frequently the white flowers have red centers.
Rose mallows are easily grown from seed. When nurseries sow them indoors in late winter, they can expect full-sized, flowering plants by mid- to late summer. For optimum growth, rose mallows need full sun and good mulching.
For sun-drenched areas, the sedums, particularly Sedum "Autumn Joy," are useful. Their individual pink flowers may be small, but they occur in large, dense clusters on top of stiff stems with very succulent leaves. "Autumn Joy" consistently ranks among the most popular of all herbaceous perennials.
Hard frosts simply transform the characteristics that give it aesthetic interest. Its original pink flowers and green foliage change to golden yellow and rusty brown in winter. And few pests bother "Autumn Joy."
Finally, gardeners should not ignore a plant that is becoming the queen of herbaceous perennials: Hosta (hosta). This plant has become, almost single-handedly, the cure for boring shade gardens. Its restorative ingredients include a myriad of foliage patterns, different leaf shapes and foliar puckering.
Hosta can be grown in sunny spots, but it must have moisture-retentive soil. It commonly forms mounding clumps that vary in height. Some species are prostrate, while others reach heights of several feet.
\ Dr. Robert E. Lyons is an assistant professor of horticulture at Virginia Tech.
by CNB