By CAROL NUCKOLS - Fort Worth Star-Telegram – Friday, October 20, 1995

           You’ve been enjoying your perennial border all season long, but perhaps some fine-tuning is in order.  Now is a good time to evaluate the border’s successes and failures, with an eye toward making improvements.

            Maybe you never imagined when you planted the hosta and lavender side by side that you would drown the lavender while trying to quench the hosta’s thirst.  Or that you would hate the way the foliage looks on those irises and amaryllises planted together: the bluish-green of iris against the yellow-green of amaryllis.

Puttering
with
perennials
puts them in
the pink

            Don’t feel bad.  Even the experts make mistakes.

            I do a lot of research before I plant anything, and yet I still make errors,” said Randy Weston, owner of Weston Gardens in Bloom in Fort Worth.  “That’s how you learn.  All of us are gonna make mistakes.”

            Weston and other garden experts offered tips on what to avoid in the perennial border, as well as winning plant combinations.

            First, some general warnings.

            “Don’t put trumpet vine anywhere near a mixed border,” Weston cautioned.  Same goes for honeysuckle, wisteria, grapevine and Vinca major.  All are invasive, and you’ll be fighting them for years.  As for bamboo: “Never, never, never, never.”

            Keep in mind the mature sizes of plants; if they’re tall, wide or particularly vigorous, they can choke out whatever’s around them.

            Plant fast-growing, thorny roses, like Mermaid, away from areas of activity.  Don’t put them in the middle of the perennial border, for example, where you’ll be cutting back spent blooms.

            And you may think that an early-blooming shrub, such as quince, should receive star treatment.  Better to exercise restraint and place it toward the back of the border, Weston suggested.  “It’ll be ugly by July and August.”

            “Think about the life cycle these things go through and place them accordingly,” he said.

            And don’t get carried away and make your border so wide that you can’t reach in to deadhead spent blooms, unless you include steppingstones or paths, he added.

            Color combinations are an obvious consideration.  “Single-color borders are the easiest to design because they guarantee a unified effect,” write the authors of Garden Design (Simon and Schuster, 1984).  Such a design needn’t be boring, though; darker and lighter variations of a single color add interest.

            For multicolor themes, the book suggests sticking to either warm or cool colors, or else a thorough mix of colors.

            Some gardeners like curving sweeps of perennials, in groups of three or five or so, said Ruth Kinsler, owner of Redenta’s Garden stores in Arlington and Colleyville.  In her own yard, she has more of a mixture – individual plants of varying colors and sizes grouped together.

            Don’t forget form.  Form refers to both the shapes of plants (such as pyramids and cascades) as well as to the shapes of flowers themselves, explains William C. Welch in his book Perennial Garden Color (Taylor, 1989).  The two basic flower forms are spike (such as salvia and gladiolus) and ray (such as daisy, coreopsis and aster).  Juxtaposing two forms can show off both to advantage.

            The same is true of texture, Welch continues.  “Texture is relative, and placing two dissimilar textures in close proximity heightens the effect of both,” he writes.

            For plants to grow compatibly side by side, they must have the same cultural requirements, such as water use and amount of sun and shade needed.

            Now for some pleasing plant combinations with similar requirements, recommended by Weston and Kinsler.

 For sun:

• Gregg’s salvia (Salvia Greggii) and Powis Castle artemisia.  The salvia’s red or pink blooms and dark green foliage contrast with the artemisia’s fine silver foliage.  Both can thrive in the hottest, driest spot in your yard.  Hummingbirds love the salvia, and the artemisia has a pleasing herbal scent.

• Powis Castle artemisia and Little Bunny fountain grass (Pennisetum alopecuroides ‘Little Bunny’) or Hameln’s fountain grass (Pennisetum alopecuroides ‘Hameln’). The grasses’ fuzzy seed heads turn golden to whitish in the fall, and their foliage turns reddish, contrasting with the artemisia’s silvery color and fine texture.

• Moonbeam coreopsis (Coreopsis verticillata ‘Moonbeam’) and Veronica (Veronica x.) ‘Sunny Border Blue’ or ‘Blue Charm.’  The Veronica’s purple or blue spikes make a stiff backdrop to the low, arching form and yellow blooms of the coreopsis.  Both bloom from spring into July.

• Mexican bush sage (Salvia leucantha) with artemisia and/or ornamental grasses.  Surround the sage, which grows up to 6 feet tall, with a ring of artemisia and a low-growing grass such as Little Bunny fountain grass.  The sage blooms purple and white or solid purple from September through early November.
  Sage also can serve as a foil to dwarf goldenrod, which grows 3 to 4 feet tall and blooms May through November; goldenrod isn’t the allergenic culprit people think it is, Weston said.

• Mexican mint marigold (Tagetes lucida) and Hill Country aster (Aster oblongifolius).  The yellow of the marigold contrasts with the blue aster; this combination can also take dappled shade.

• American beautyberry (Callicarpa Americana) and Turk’s cap (Malvaviscus arboreus).  Beautyberry grows to 10 or 12 feet but can be pruned to 4 or 5 feet; Chinese beautyberry is a 3- to 4-foot alternative.  The deep reddish-purple berries mature in fall.  Turk’s cap blooms red May through frost.  Both can take full shade as well as full sun.  Turk’s cap with pink-blooming obedient plant (Physostegia virginiana) is another good fall combination.

• An upright coreopsis or Mexican mint marigold and little bluestem (Schizachyrium scoparium).   Lanceleaf coreopsis (Coreopsis lanceolata) grows to 4 feet; (Coreopsis grandiflora) ‘Sunray’ and ‘Early Sunrise’ are more compact varieties.  The yellow flowers contrast with the upright grass’ steely blue-gray, which turns coppery orange in the fall.  If you keep the flowers watered, they’ll still be in bloom when the grass turns colors.

• Purple coneflower (Echinacea purpurea) and gaura (Gaura lindheimeri).  Plant gaura, which grows 3 to 5 feet tall, behind the coneflower.  Gaura is very lacy and airy, with tiny white blooms all summer long – a nice background for the coneflower’s large blossoms.

• Lamb’s ears (Stachys byzintina) and Mexican petunia (Ruellia brittoniana).  Plant the 12- to 18-inch, silvery lamb’s ears in front as a foil for the taller purple flower.

• Black-eyed Susan (Rudbeckia fulgida ‘Goldsturm’) and silver mound artemisia.  The black-eyed Susan blooms reliably through the summer; plant the artemisia in front.

For shade:

• Inland sea oats (Chasmanthium latifolium) and Turk’s cap or obedient plant.  The grass’ nodding seed heads mature during the fall, when the Turk’s cap and obedient plant are in bloom.

• Hostas and ferns.  “All ferns look good with hosta leaves,” Weston said.  Tassel fern (Polystichum polybletharum), with its unusual foliage, and the evergreen holly fern (Cyrtomium falcatum) and autumn fern (Dryopteris erythrosora) are among his favorites; so is wood fern (Thelypteris kunthii), more drought-tolerant than most, and Japanese painted fern (Athyrium niponicum ‘pictum’), whose silver-green foliage works well with dark green hostas.  Some favorite hostas include Old August, Francee, Francis Williams, Royal Standard and Blue Boy.  Hostas and ferns need good bed preparation, mulch and constant moisture.
  Two varieties of coral bells – (Heuchera Americana), with pinkish flowers that stand above the mottled oval leaves, or Heuchera micrantha ‘Palace Purple,’ with purple foliage and white flowers – are other good choices with ferns.

• Oakleaf hydrangea (Hydrangea quercifolia) and cast-iron plant (Aspidistra elatior).  The hydrangea, which can reach 10 to 12 feet, blooms in the spring, bears decorative seed pods in the summer and turns crimson in fall.  Cast-iron plant can take bad soil and drought.

• Katie’s Mexican Ruellia (Ruellia brittoniana ‘Katie’s’) and strawberry geranium (Saxifraga stolonifera).  The Ruellia, 10 to 12 inches tall and wide, with a strap-like leaf and light lavender blooms, contrasts with the trailing dark blue-green leaves and airy white blooms of the geranium.

• Columbines and wood violets (Viola missouriensis).  The yellow-blooming Hinckley columbine (Aquilegia Hinckleyana) or yellow and red Aquilegia Canadensis, 2 feet in height, tower over the low-growing violets.

• Hardy ageratum (Eupatorium coelestinum) and Mexican mint marigold.  The ageratum, which grows 2-3 feet, blooms pale blue in fall, until frost; the Mexican mint marigold grows up to 3 feet.