During the early weeks of June, our perennial borders attain their ultimate splendor as multitudes of showy colorful blossoms paint the landscape with cheerful abandon.

During the early weeks of June, our perennial borders attain their ultimate splendor as multitudes of showy colorful blossoms paint the landscape with cheerful abandon.


Attractive mounds of perennial geraniums; captivating Canterbury bells; clumps of Siberian iris; fringed bleeding hearts; purple, pink and white salvias; dainty coral bells; delicate dianthus; and dramatic foxgloves all join the floral parade this month.


The massive blooms of flamboyant peonies glow from afar in shades of pink and coral, red and white. Nearby, the fleeting tissue-paper blossoms of oriental poppies sway in the breeze on long wiry stems. Exquisite irises splash rainbow colors throughout the border, creating a spectacular display as summertime warmth continues to accelerate our springtime blooms.


Few hardy perennials exhibit the singular beauty of a perfectly formed bearded iris blossom. Resembling giant orchids, these alluring, sun-loving plants are available in a broad array of colors and patterns, distinguished from other members of this family by the fuzzy beard, which appears on their lower petals. Broad, blue-green, sword-like leaves emerge as fans from a thick, fleshy rhizome.


Bearded irises perform optimally in full sun and very well-drained soils to which lime has been added; poor winter drainage often leads to rotting or heaving out of the ground. The upper portion of the rhizome should be exposed to sunlight when planting and mulches should not be allowed to cover the rhizome. Division is best performed every three to four years during August.


In recent years, the low-maintenance Siberian iris family has become my iris of choice. Hybridization efforts have produced a broader range of colors including pale, lavender-pinks, rich burgundy reds, pale yellow, glistening whites, and many shades of blue and purple -- in addition to significantly larger flower sizes.


Unlike the sword-like, blue-green leaves of bearded iris, Siberian iris form more of a grassy clump from which dozens of slender stems emerge, bearing flowers 2 to 6 inches wide. Tolerant of most soils, they perform best in sun to partial shade in acidic, moisture-retentive soils. Clumps should be divided periodically in early spring or September or they may develop woody centers with fewer blooms.


Herbaceous peonies are exceptionally long-lived perennial favorites with handsome foliage throughout the growing season -- topped with voluptuous blooms during the month of June. Moisture-retentive soils in full sun are preferred, although they will tolerate a little shade.


In addition to the popular double-flowering forms, single and semi-double blossoms are available with colors ranging from deep red, shades of pink and coral, and white. This year’s display should be one of the best ever with nearly all clumps covered with dozens of plump buds.


Since Murphy’s Law dictates that when the massive double peonies come into bloom there will be torrential downpours, double-ringed peony support hoops are highly recommended to prevent the beautiful blossoms from sprawling in the mud. Plants that fail to produce flower buds may be planted too deeply (the reddish-pink buds on peony roots, referred to as “eyes”, should be approximately 2 inches below the soil surface), receive insufficient sunlight, or may be starved of nutrients due to excessive root competition from nearby plants or soil depletion over many years. Division or transplanting should be performed in autumn.


Attractive companions for the iris, poppies and peonies are provided by the statuesque spires of the Baptisias.


These long-lived, low-maintenance American natives offer attractive pea-like flowers in shades of blue in addition to yellow and white forms against a backdrop of handsome blue-green, pea-like foliage. Most varieties grow 3 to 5 feet tall given average soil in sun or light shade.


I am fond of a white form, B. pendula (named for its pendulous seedpods) that resembles gray asparagus when it emerges in springtime and produces phenomenal white spikes, and B. sphaerocarpa with shocking yellow blooms. Other appealing cultivars include the soft creamy yellow "Carolina Moonlight," "Purple Smoke," and a purple and yellow bicolor, "Twilight Prairie Blues," with more color breakthroughs on the horizon.


Hardy perennial geraniums (not to be confused with the popular annual bedding plant, Pelargonium) are a diverse family of plants that offer attractive foliage and blooms for the front or middle of the border.


The bloody cranesbill, G. sanguineum (named for its beak-like seed heads), forms mounds of lovely divided foliage topped by a profusion of 1-inch magenta flowers; leaves acquire a handsome red hue in autumn. I prefer the white (G. alba) or pink with rose veining (G. striatum) forms better for blending with other colors in the June border. Full sun and moisture-retentive soils are best.


The big-root geranium (G. macrorrhizum) furnishes a carpet of large, slightly fuzzy leaves with purplish, magenta flowers; its greatest attribute being its tolerance of semi-shady locales and drought -- making it an ideal candidate for growing amongst greedy tree roots.


Perhaps the best of all is Geranium "Rozanne." Attractive lobed leaves are slightly marbled and looked great all summer while its flowering stems gradually elongate over the season, weaving their way among neighboring plants, giving the appearance of knitting surrounding companion plants together. Beginning in June, dozens of saucer-shaped blossoms are produced above an expanding 20-inch mound. The pleasing, 2-inch reddish-purple flowers fade to a deeper blue with white centers during the cooler times of the day and later in the season with persistent blossoms until frost.


Nurseries still have an excellent supply of colorful perennials to brighten your June borders. Add several of these hardy plants this spring and enjoy their beauty for years to come. 


Suzanne Mahler is an avid gardener, photographer and lecturer who has been developing the 1.5-acre property surrounding her home in Hanover, Mass., for more than 30 years. She is a member of two local garden clubs, past President of the New England Daylily Society, an overseer for the Massachusetts Horticultural Society and is employed at two garden centers.