Spring 1998

Sensational Siberian Iris	Plant Combinations: Vernal and Autumnal Alliances	Spring Foliage Effects
Plantsmen Remembered	Tranquil Lake Hosts Tour	*1998 Perennial Plant of the Year: Echinacea purpurea* 'Magnus'**

Sensational Siberian Iris

Named after Iris, the Greek goddess of the rainbow, the perennial by the same name has a noble patroness to follow. Siberian iris are up to the task. They live up to this standard with regal beauty and low-maintenance hardiness.

Siberian iris are native to moist meadow areas in central Europe and east-central Siberia. They are one of several species of beardless iris, and have fibrous-root systems, unlike their bearded relatives that possess fleshy rhizomes. Siberian iris tolerate damp conditions and even water-logged soil. They are also quite happy in well-drained loam soils amended with organic matter and topped with a moisture-saving mulch. Established clumps are quite drought-tolerant. Full sun locations are best for a profusion of flowers.

Siberian iris flowers are distinctive in structure and form from most other blooms. A stylized Siberian iris flower, the Fleur-de-lis, was the emblem of French royalty. The design of this majestic inflorescence consists of three outer petals that hang downwards, known as falls, and three erect petals called standards. In addition the flower contains three colorful styles, between the standards and falls that are petal-like in appearance.

The color of species Iris sibirica, is blue-violet, with a blaze or signal pattern on the falls veined brownish- yellow. Hybridizers have created many color variations ranging from shades of blue ('Rosace') to lavender-pink ('Lydia Winter') and wine-red ('Ewen'), snow-white ('Illini Peace') and even the color breakthrough - primrose-yellow ('Butter & Sugar'). The color patterns on the standards, falls and styles may be a solid color (self) such as 'Pirate Prince', or veined and mottled like 'All in Stipple'.

The color pattern of white standards and colored falls is known as an "amoena". It is common in bearded iris hybrids but rare in Siberian iris. 'Yankee Doodle Boy' has such a color break with light-blue standards fading to white over darker blue falls with white styles.

Siberian iris bloom from late May through June. 'Yankee Doodle Boy' is one of several varieties that will rebloom in late July and August with sufficient moisture. Siberian iris have reed-like, green foliage that is attractive long after the blooms have faded. This combination of flowers and foliage lends to a long season of pleasing combinations in the mixed border.

Combine violet-blue 'Marilyn Holmes' with pale-yellow Achillea 'Moonshine', blue Campanula persicifolia and blue oat grass (Helictotricon) for colorful flowers and foliage. In a damp location Filipendula ulmaria, Iris 'All in Stipple', Trollius, Aconitum, and Acorus gramineus 'Ogon' light up the garden. Plant Siberian iris this spring for a delicate regal splendor.

"May and December romances" in the mixed perennial border are celebrated for their dynamic and sophisticated qualities. Careful plant pairings from opposing seasons will offer the opportunity for a longer display time filled with colorful combinations in your mixed border.

A classic example of a polar-seasonal relationship is a double-planted border of spring blooming daffodils and late-summer flowering daylilies. Daffodil foliage must be left uncut, even after the blooms fade, to nourish their bulbs and ensure their longevity. The maturing and unsightly daffodil foliage often persists into June, tempting the gardener with their ever-ready shears. A companion planting of daylilies offers fresh verdant green leaves to mask the offending daffodil foliage.

The yellow trumpets of Hemerocallis 'Three Seasons' continue to herald the daffodil's pageant of golden color into the late-summer garden. In our garden, Ligularia dentata 'Desdemona' also offers a lively liaison with spring blooming daffodils. Desdemona's round, maroon leaves emerge with a fanfare to complement the pale yellow Narcissus 'Lunar Sea'. The striking foliage display of Ligularia dentata 'Desdemona' continues to escalate, building up to a crescendo in August with blooms of golden daisies on purple stems above maroon-tinged peltate leaves.

Some spring-blooming perennials, such as bloodroot, are ephemeral and disappear from the summer garden. Others, like lungwort (Pulmonaria saccharata varieties), have persistent and beautiful foliage to enhance a late-season arrangement. The silver-spotted leaves of Pulmonaria 'Mrs. Moon' and the September flowers of toadlilies (Tricyrtis) make a becoming pair in a partial-shade bed. Add the enormous chartreuse leaves of Hosta 'Sum and Substance' and the yellow, late-August bells of Kirengeshoma palmata for an amazing menage.

In a sunny border, Euphorbia varieties display vivid, chartreuse-colored bracts in early spring and handsome foliage throughout the rest of the year. Two exceptional species for their 'evergreen' attributes are Euphorbia myrsinites and Euphorbia amygdaloides 'Purpurea'.

The myrtle leaf spurge (E. myrsinites) sports succulent, blue-green whorled leaves on a low sprawling plant. Combine it with the airy panicles of sea lavender (Limonium latifolium) and blue, balloon flower (Platycodon grandiflorus) for a drought-tolerant, long-lasting, blue streak in the border.

Euphorbia amygdaloides 'Purpurea' has maroon-cloaked leaves that furnish a neat twelve-to-eighteen inch high mound. This Euphorbia's maroon foliage is both a pleasing contrast to the grey-green leaves of Sedum spectabilie 'Brilliant' and a complement to its pink flowers in September. Add to this pair, October blooming Aster lateriflorus 'Horizontalis' or Aster novae-angliae 'Purple Dome' and yellow-green Molinia caerulea 'Variegata' for a color combination mirrored in the spring and fall border. Euphorbia amygdaloides 'Purpurea' has maroon-cloaked leaves that furnish a neat twelve-to-eighteen inch high mound. This Euphorbia's maroon foliage is both a pleasing contrast to the grey-green leaves of Sedum spectabilie 'Brilliant' and a comple- ment to its pink flowers in September.

Add to this pair, October blooming Aster lateriflorus 'Horizontalis' or Aster novae-angliae 'Purple Dome' and yellow-green Molinia caerulea 'Variegata' for a color combination mirrored in the spring and fall border. Euphorbia amygdaloides 'Purpurea' has maroon-cloaked leaves that furnish a neat twelve-to-eighteen inch high mound. This Euphorbia's maroon foliage is both a pleasing contrast to the grey-green leaves of Sedum spectabilie 'Brilliant' and a comple- ment to its pink flowers in September. Add to this pair, October blooming Aster lateriflorus 'Horizontalis' or Aster novae-angliae 'Purple Dome' and yellow-green Molinia caerulea 'Variegata' for a color combination mirrored in the spring and fall border.

The colorful leaves and blue flowers of Ajuga reptans 'Burgundy Glow' nicely match the blue tussocks of blue-oat grass (Helictotrichon sempervirens). Put this duo in the front of the sunny border as a foil for Coreopsis 'Moonbeam', Hemerocallis 'Stella de Oro' and blue beard (Caryopteris x clandonensis). In moist shade, combine Dicentra spectabilis and Aconitum. Lyre-shaped blooms adorn the old-fashioned bleeding heart in the spring. The sturdy and attractive foliage of monkshood, Aconitum 'Barker's 'Barker's Variety' commodate any void left by its mate in the late season, and its deep-violet blooms will fill in the void left by Dicentra in the late season.

Many woody shrubs offer an amicable alliance that complements the bloom seasons of herbaceous perennials. The following shrubs are some of the earliest to leaf in the spring: barberry (Berberis thunbergii 'Rose Glow'), golden ninebark (Physocarpus opulifolius 'Luteus'), variegated elderberry (Sambucus nigra 'Madonna') spirea (Spiraea x Goldflame and Spiraea japonica 'Goldmound') and the earliest spring foliage is the pinnately compound leaf on Ural false spirea (Sorbaria sorbifolia).

Late blooming asters are excellent partners for spring-shrubs. Statuesque Aster tataricus, with six-foot high blooms in October, is a match nestled next to the yellow leaves of ninebark. Spiraea japonica 'Goldmound' is distinguished by its low mound of golden foliage. The bright leaves are a complement to the blue flowers of grape hyacinth (Muscari) in May as well as the dwarf from of New England aster, Aster 'Purple Dome' in October.

Aronia arbutifolia 'Brilliantissima' is a native shrub with ornamental attributes during every season. Spring clusters of white flowers are followed by red fruit that last all winter and red fall foliage. Combine Aronia with the September blooming feather-reed grass (Calmagrostis brachytricha) and Boltonia asteroides 'Snowbank'. Plant Helianthus angustifolius with Cornus 'Silver & Gold' and Panicum 'Heavy Metal', trollius and Iris sibirica. Aronia arbutifolia 'Brilliantissima' is a native shrub with ornamental attributes during every season. Spring clusters of white flowers are followed by red fruit that last all winter and red fall foliage. Combine Aronia with the September blooming feather-reed grass (Calmagrostis brachytricha) and Boltonia asteroides 'Snowbank'. Plant Helianthus angustifolius with Cornus 'Silver & Gold' and Panicum 'Heavy Metal', trollius and Iris sibirica.

Merge your spring and fall plantings to complement each other, and extend the beauty of the mixed border.

This past year marks the passing of three hybridizers and plantsmen that we at Tranquil Lake Nursery have had the pleasure to know, learn from and share their beautiful plant introductions with many gardeners.

Allen P. McConnell's enthusiasm for horticulture was truly diverse. He was an early member of the Iris Society as well as an active member of the Daylily Society and Hosta Society. He had a discerning eye for quality. Hosta 'Allen P. McConnell' has long honored his namesake and is a memorial shared in gardens nationally. Allen also selected a regional form of Iris pseudacorus 'Lonesdale'.

Dick Webster of Arab, Alabama was a daylily hybridizer whose name is a symbol of quality. He is known for hardy and beautiful introductions as well as unique tetraploid spider and spider variants daylilies, such as 'Fire Arrow' and Galaxy Star'. His memory, like his plants, will continue to live on in our gardens.

Lud Hoffman, of Bloomfield, Connecticut, was a horticultural mentor to many, including Warren. He was the epitome of a plantsman, nurseryman and had an eye for beauty and design. Lud's collection of plants showed his depth of knowledge in herbaceous perennials, rock garden gems, dwarf conifers and other woody trees and shrubs. He will also be remembered for his beautiful mountain. laurel, especially one he named Kalmia latifolia 'Nathan Hale', a pink budded type with beautiful foliage and a compact habit.

Tranquil Lake Nursery will be one of the host sites for the National Meeting of the Perennial Plant Association Tour on July 10th and 11th. To prepare for the tour we have made lots of changes this year. You will see new paving and new garden areas when you visit the nursery.

Purple cone flower, Echinacea purpurea, is a beautiful drought- tolerant perennial native to the prairie. The daisy-like flowers sport rosy purple petals around an orange tinged central cone. Purple cone flower blooms from July through September. Echinacea purpurea 'Magnus' is a cultivar with large flowers and non-drooping petals. A great attraction for butterflies in the garden.