Centaurea Montana: A Cottage Garden Favorite

Centaurea montana captured my interest many years ago, when I saw it in the garden of the Holliston Historical Society. The flowers of this Mountain Bluet were similar to the annual cornflower that I had grown from seed, but they were much larger, on a plant sporting silvery, fuzzy leaves and a bushy habit. Best of all, Centaurea montana was a perennial, so it would not need to be planted every year. I was sold, and shortly acquired three plants of my own.

Centaurea montana, also called “Perennial Bachelor’s Button”, has been flowering in gardens for centuries. Equally at home in cottage gardens or more naturalized settings, Centaurea is an old-fashioned flower with a relaxed habit, and long-lasting, boisterous blooms that are equally charming in a vase as they are in a garden bed. Its bright blue flowers open from attractive buds in late spring, then leave behind a mass of vigorous, silvery-green woolly foliage. In my early summer garden, the cornflower hue complements the blues of baptisia, geranium ‘Johnson’s Blue’, salvias and alliums, and contrasts with the bright yellow blooms of ‘Stella d’Oro’ daylilies, sundrops, and the foliage of dicentra ‘Gold Heart’ and lamium ‘Cannon’s Gold’.

Centaurea’s history extends all the way back to ancient Greek mythology. When Chiron the Centaur was wounded by one of Hercules’ poisoned arrows, he was cured by this herb’s amazing healing powers. In times past, Centaurea was appreciated for its astringent herb qualities, and its flowers were used to treat minor wounds, mouth ulcers and eye ailments such as conjunctivitis. Today, extracts of the plant are used in shampoos and conditioners.

As a garden plant, I have found Centaurea montana to be a versatile perennial that grows best in full sun to light shade in ordinary garden soil. It tolerates drought once established, but will not thrive in waterlogged conditions. Its short stature makes it ideal for the front or middle of a perennial border. Centaurea blooms in late May to late June, at which point I cut it back to secondary stems for continued blooms. Once the plant starts to look ragged in mid-summer, I trim back the stalks to the basal leaves, and wait for a second flush of blooms in late summer. After flowering, Centaurea montana self-seeds freely, creating welcome drifts in cottage gardens. I always have enough plants to share with friends but not so many that I find it invasive.

New hybrids of Centaurea montana have recently been introduced. ‘Amethyst in Snow’ has silky white blooms with royal purple centers. My friend Kathy grows this Centaurea in a garden filled with dark purple bearded iris, purple heuchera, and Rhododendron ‘Calsap’, with its striking white blossoms adorned by a dark purple splotch. Echoes of purple and white accented by chartreuse and yellow create a garden that is energetic and fresh.

Another new cultivar of Centaurea Montana is ‘Gold Bullion’, a dramatic combination of electric yellow foliage, black-etched buds, and lacy, bright blue flowers.

‘Black Sprite’ is a dramatic hybrid with purplish black flowers that bloom from July to August and would look terrific underplanted with Black Mondo Grass. Whether you prefer the cottage look of the original cornflower blue Centaurea, or the modern appeal of ‘Black Sprite’, Centaurea montana will add an interesting twist to your summer garden.

The Mayapple: A Native Woodland Colonizer

During my first visit to Monticello last month, I came across a wonderful book that piqued my interest in native plants. Andrea Wulf’s highly engaging The Brother Gardeners brings to life the science and adventure of eighteenth-century plant collecting, beginning with colonial farmer John Bartram who started shipping seeds of our native plants to English collectors in 1733. English plant lovers were entranced by the hundreds of unusual American trees and shrubs, from magnolias and firs, to rhododendrons and mountain laurels, to the wildflowers of the woodlands and prairies. Since Bartram lived in Pennsylvania, one of the perennials that he must have sent to England was our native Mayapple, Podophyllum peltatum, which is currently blooming in my garden.

Mayapple is yet another spring ephemeral – a perennial woodland wildflower that blooms early in the spring (May in Massachusetts), sets seed and then disappears by midsummer. Native in eastern North America south to Texas, Mayapple is hardy from zones 3 to 8, and makes a lovely addition to the woodland garden. The plants poke out of the ground looking like shiny little folded umbrellas, and then quickly unfold. From a single stem, each plant grows 12-18” tall, and produces one or two umbrella-like leaves that may be up to 12” in diameter. The leaves are deeply-divided, and a mass of Mayapples looks like a grove of miniature palm trees.

Mayapples are unique in that they have a solitary flower, which forms in the axil of the leaves. The nodding, white flower sports 6 to 9 waxy petals, and resembles an apple-blossom. (A rare new pink-flowered form, ‘Missoury May’, has recently been introduced and is available through specialty nurseries.)

The 2” blossom is usually hidden by the large leaves, so you have to get down low to appreciate its delicate beauty. After the flower is pollinated by bumblebees, each plant produces a fleshy, greenish lemon-shaped fruit (the apple) which turns golden when ripe. The fruit can be used for preserves and jellies, and apparently tastes like an overripe melon. However, since the rest of the plant—the leaves, roots, and unripe fruit—is highly toxic, I have not sampled it myself.

Mayapples are best grown in partial to full shade, in rich, well-drained, humusy soil. They will tolerate dry soil and drought once established. The plants colonize by underground stolons, forming dense mats. They do not like heavy competition from other plants. Although it is recommended that they be grown under deciduous trees, mine are growing well under the canopy of 75-foot tall Norway spruces. They are toughing it out in the company of mammoth hostas, bloodroot and Christmas ferns.

Mayapples may be propagated by root division while dormant in the fall. Each new division should have at least one bud. The plants will also self-sow in optimal growing conditions, but seedlings take several years to mature. Like trilliums, Mayapples should be enjoyed them in the garden, not in a vase. Picking the flowers is impossible without cutting the leaves as well, and the plants need the leaves to supply fuel for next year’s growth.

For gorgeous displays of Mayapples and other native woodland wildflowers, visit Garden in the Woods this month, the Framingham, Mass. home of the New England Wildflower Society. In addition to special programs, Garden in the Woods offers many unusual plant cultivars for sale, and is a great place to start your own native American plant collection.

Dwarf Crested Iris Brightens the Spring Garden

After a week of much-needed spring rain, the garden looks lush and expectant. Everywhere, there seems to be a new wonder to appreciate and admire. Hosta leaves unfurl, the blossoms of the crabapple trees are buzzing with bees, and the arching stems of old-fashioned bleeding heart are lined with dangling blooms. And, hugging the ground, a drift of dwarf crested iris offers delicate charm.

Dwarf crested iris (Iris cristata) is a small iris, less than 6 inches tall in bloom, with 2- to 3-inch wide flowers that hover just above its blade-shaped foliage. It spreads by creeping rhizomes, eventually forming a dense groundcover. It is one of the most common of the irises that are native to the northeastern United States. It can be found growing on stream banks and on wooded slopes or rocky bluffs in its native habitats. Despite its delicate appearance, it is a tough little plant that is extremely hardy (Zones 3-9).

Most people are familiar with the tall bearded iris. The flowers of the dwarf crested iris are beardless. They are very showy, with three narrow petals and three broad, down-curved sepals. The sepals are centrally marked with a yellow or white band, with a crested ridge and a white splotch. Flower color is typically shades of blue-lavender, deep violet or white.

Iris cristata ‘Alba’ is the white form of the dwarf crested iris. The flowers are a particularly bright white color that is outstanding in moon gardens. Its softly spiky form and clear color enhance other garden plants. I have planted it in front of a yellow-leaf bleeding heart (Dicentra ‘Gold Heart’), a green-edged yellow Hosta (‘Golden Meadows’) and a dark pink azalea (‘Renee Michelle’); just dazzling.

Other garden-worthy Iris cristata cultivars include the dark purple ‘Navy Blue Gem’ and ‘Eco Purple Pomp’, the light blue ‘Powder Blue Giant’ and the ruffled blue ‘Shenandoah Sky’.

Dwarf crested iris prefers well-drained soil with moderate fertility and moisture. It will tolerate drought once established. It performs well in sun or shade, but does best in part-shade. When planted in sun, it requires extra moisture.

Its ability to perform well in shade increases its usefulness. When planted in both sunny and shady areas of the perennial border, it helps create unity through repetition. At the shaded end of my mixed border, I have planted it amongst ferns, Epimediums and hostas (H. ‘Yin’ and H. ‘Allegan Fog’). In a sunnier location, it keeps company with assorted campanulas, Heuchera ‘Venus’ and Sedum ‘Autumn Joy’.

Dwarf crested iris is an excellent plant for the home garden. It is lovely planted along the edge of a path or perennial border. It will naturalize in woodland gardens, where it will produce great swaths of springtime color. Like all irises, it is deer resistant. It will grow and bloom in dry shade.

By Joan Butler

Woodland Phlox: A Natural Mingler

To many gardeners, the name phlox conjures up images of a fragrant perennial in the sunny mid-summer border. There is another phlox, however, Phlox divericata, that creates a cloud of shimmering blue and violet in woodland shade.

Woodland phlox is a delightful spring-blooming native that forms a creeping mound about one foot tall. As the common name suggests, it is a woodland wildflower, growing in forests, fields, and alongside streams. It prefers light to full shade, moist soil and a summer mulch of shredded leaves or bark. The foliage forms a mat of loosely entwined stems with semi-evergreen oblong leaves. The stems are both hairy and sticky.

Although its foliage does not have a strong presence, Woodland phlox makes up for this with ethereal drifts of flowers, in hues ranging from sky blue to violet, to rose and soft white. The sweetly scented blooms are formed in loose clusters of tubular flowers, each up to 1.5" wide, with five flat, notched, petal-like lobes that appear at the stem tips.

Woodland phlox is a natural mingler, chatting its way across the woodland floor. It weaves in and out of neighboring flowers, complementing spring flowering bulbs and providing a carpet for taller perennials.

As the leafy shoots spread along the ground, they root at the nodes, creating nice colonies. It is a great plant for naturalizing since it also self-sows to create soft drifts that blend well with other woodlanders.

Woodland phlox is what landscape design guru Piet Oudolf would call a “filler plant”. Plants are either “structure” or “filler” plants depending on their form, shape and texture. Structure plants have outspoken personalities that dominate their neighbors, while filler plants, which lack a strong presence of their own, weave around the others and fill in gaps. Filler plants like Woodland phlox, with its creeping form and soft hue, are vital to the garden, creating a seamless flow in the overall design.

Desirable cultivars of Phlox divericata include ‘Clouds of Perfume’ with its pronounced fragrance and  powder-blue flowers; ‘May Breeze’, a soft-white phlox introduced by Piet Oudolf, and ‘Blue Moon’, the favorite dark blue selection of Bill Cullina, curator of the Coastal Maine Botanical Garden.

Beautiful Bold Bergenias

Plants with “multiple seasons of interest” are all the rage in gardening circles, and for me, Bergenias fit the bill. Most Bergenias are evergreen perennials that remain attractive all year. Their rounded, bold leaves set off the feathery foliage of ferns and conifers, the slender leaves of iris, or the small oval leaves of boxwood.

As cooler weather sets in, the leaves develop rich winter coloring, ranging from purple to maroon, crimson, bronze and even beet red. Popular in Europe, these valuable plants have been largely neglected by American gardeners. If you want to add a lush, elegant, easy-care plant to your garden this spring, look for a Bergenia.

Bergenias are native to central Asia, from Afghanistan to China and the Himalayas, and belong to the Saxifrage family – closely related to Heucheras, Astilbes, Tiarellas, Rodgersias and Mukdenias. Most members of the Saxifrage family have a flower cluster held well above their basal whorl of leaves, and many grow in rocky places, hence the scientific name which means “stone breaker”. Bergenias were named in honor of the 18th century botanist Karl August von Bergen. Like other garden plants, Bergenias have inherited colorful common names that illustrate their traits: “elephant ears” for the shape of their leaves, and “pigsqueaks” for the sound that you get when you rub their leaves with your fingers.

There are ten different species of Bergenia with variations in plant height and flower colors. I grow the most popular species – Bergenia cordifolia, with its heart-shaped leaves. The plants are about 18” tall, with evergreen foliage that turns a rich burgundy color in fall and winter. In late April, red stalks produce beautiful clusters of bell-shaped pink flowers and the leaves turn to a rich glossy green. In my garden, Bergenia’s large, leathery leaves complement the finely cut maroon foliage of a ‘Crimson Queen’ Japanese maple, a small-leaved boxwood, purple coral bells and pink peonies.

I originally planted three Bergenias, which have slowly multiplied to a drift of about twenty-five. The plants grow from long, tube-like underground roots called rhizomes, and can be divided every 2-3 years to avoid crowding and ensure the best blooms. Mine enjoy a partly shaded, sloped bed, which provides excellent drainage. Other than trimming any tattered leaves in the early spring, and deadheading spent flower stalks, the plants are totally carefree. In general, Bergenias are very cold-hardy, thriving in zones 3-7 in the Eastern U.S. They prefer a somewhat protected location, however, since winter winds will scorch and tear their large evergreen leaves. I have two clumps growing on either side of a low evergreen shrub, and the windward clump always looks more haggard in the spring than the leeward clump.

Although Bergenias are outstanding foliage plants, you can find variations in bloom color from white to ruby red and purple. Interesting varieties include ‘Bressingham White’ (white blooms), ‘Baby Doll’ (baby-pink), ‘Apple Blossom (pale pink with red calyx) and ‘Eroica’ (reddish pink).

For something completely different, you can grow one of the recently introduced variegated cultivars. ‘Tubby Andrews’ is green streaked with gold and cream, while ‘Solar Flare’, is similar to a hosta, with a green center and irregular cream and yellow margins. Both sport dark pink blooms. When the cold weather hits, the foliage of these plants takes on various tints of pinks and reds, creating a real showstopper in the garden.

No matter which Bergenia you choose, you will be rewarded with many seasons of beauty in your garden.

Liriope’s Stripes Add Flair and Finesse

One of the benefits of belonging to a garden club is that you are often introduced to new plants. Gardeners are generous folks and enjoy sharing their plants, especially when they are redesigning a garden bed to make room for new acquisitions. Healthy gardens produce a bounty of perennials that need division from time to time, and most gardeners cannot bear to toss their divisions into the compost pile. So, if there is an overflow of a particular plant, babies will be potted up and either donated to the annual plant sale, or brought to a meeting and shared with other members. That is how I came by one of my favorite perennials for the winter garden – variegated liriope.

Sometimes known as lilyturf or monkey grass, liriope is a grass-like flowering perennial from East Asia. It may be either solid green or variegated, and has been widely used in the South as a groundcover due to its hardiness in Zones 6-10. Now that much of Massachusetts is reclassified as Zone 6, it is sure to be used much more widely here as well.

Variegated liriope grows to about 12” tall, with leaves striped in white or gold. It blooms in late summer with lavender, purple or white spikes that are followed by clusters of bluish-black berry-like fruits. With its foliage holding well through the winter, variegated liriope is an ornamental perennial for most of the year.

There are two species of liriope, which dictate its use in the garden. The first is liriope muscari – a clumping perennial with typically lavender or purple blooms. Because it stays where it is planted, liriope muscari is the preferred choice for flower beds or as an edger. It combines beautifully with evergreen shrubs such as boxwoods, and with perennials with contrasting leaf shapes, such as large-leaved hostas and hellebores. Variegated cultivars include ‘Silvery Sunproof’, ‘John Burch’ and ‘Gold Band’.

Liriope spicata is the “running” liriope, a vigorous grower that spreads rapidly by underground rhizomes. It will quickly cover a wide area, making it an excellent groundcover, and can be used to retain soil on slopes and banks. It is tough enough to be planted in dry shade around trees and at the edges of walks or roads. Spicata’s flowers are slightly smaller than muscari’s, and range from white to lavender. ‘Silver Dragon’ is a variegated cultivar whose foliage and lavender flowers light up shady areas.

Variagated liriope is a deer-resistant, low-maintenance perennial. It can be grown in both sun and shade, but looks best in partial shade where its color is not diminished by lack of sunlight or washed out by an overabundance of it. It requires well-drained soil, and is moderately drought tolerant when established. I treat it just like my other perennials: amend the soil with compost when planting, fertilize once a year in the spring, and top off with a layer of mulch to retain moisture. Since the foliage stays evergreen throughout winter, I trim it off in early spring before new shoots emerge. As the plants grow and mature, they can be dug and divided to increase your supply. This is usually done in the spring, every three years or so, but is not necessary for the health of the plant. However, if you need to make room for a coveted new addition to your garden, variegated liriope divisions are sure to be a welcome gift to friends and neighbors.

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Hellebore Foetidus: A True Winter Charmer

When I first became interested in hellebores, Hellebore foetidus was not at the top of my acquisition list. After all, who would want to brush by a “stinking hellebore’ in their garden? Luckily, I couldn’t resist a beautiful healthy specimen at the local big box store one day, and the Stinking Hellebore has become one of my favorite perennials to grow and share.

Although fairly common and easy to find in nurseries, Hellebore foetidus is not widespread in home gardens. It is one of the most interesting hellebores to cultivate, however, especially if you live in the Northeast. Few hellebores are as showy during the late fall and winter, when most perennials are chilling underground. Hellebore foetidus stands proud and tall, looking like a miniature rhododendron. The plant is 2’ tall with spidery evergreen foliage that remains a lush dark green throughout winter. Certain varieties also have distinctive red markings on the stems and along the deeply divided leaves. The bear-claw shape of its leaves has produced a second common name – ‘Bear’s Foot’. The distinctive foliage texture makes this hellebore an interesting companion to almost any plant in the garden.

The icing on the cake are the Stinking Hellebore’s chartreuse bell-shaped buds and flowers that perch proudly atop its beautiful foliage. How many plants boast more than 6 months of bloom, starting in November? Just as the rest of the garden hunkers down for the winter, the Stinking Hellebore forms lush pale green buds that open into clusters of l” flowers with chartreuse bracts. In the early spring, these blossoms are covered with early pollinators that help to disperse the seeds.

After a couple of years in the garden, I was very excited to find baby hellebores growing in the shade of the mother plants, and transplanted a few to my nursery bed to see how they would grow. Like other caulescent hellebores, the Stinking Hellebore is fairly quick (by hellebore standards) from seed to bloom, often blooming in its second year. Mine grew into stout little plants that first season, and I transplanted them into a new area of the garden. Since that time, I have been careful not to mulch around the hellebore plants, and have impressive colonies of both  Helleborus foetidus and niger in my shade bed. Stinking Hellebore plants can be short-lived, so it’s good to let them set seed to provide a constant supply of new plants.

Helleborus foetidus prefers woodland conditions with deep, fertile, moist, humus rich, well-drained soil, and dappled shade. The species is, however, drought tolerant once established. Plants should be shielded from winter winds. Stinking Hellebore has no serious insect or disease problems and all parts of the plant are poisonous, so it is not bothered by deer or voles. And what of the smell? I have found the plants to have a mildly unpleasant odor when bruised, but the scent of the flowers does not deter me from cutting them for a vase. I just don’t keep them on my bedside table.

Hellebore foetidus has many uses in the landscape. With its intriguing, finely cut, dark green foliage, it makes an interesting and nearly evergreen groundcover for average to dry shade. It is also impressive as a single specimen when given plenty of sun. I grow mine in two partly shaded entry gardens with other hellebores, variagated liriope, leucothoe ‘rainbow’ and hostas, where its distinctive form, texture and bloom welcome visitors all through the year.

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Hellebore 'Snow Bunting' is Sure to Please

Hellebore 'Snow Bunting' is one of my favorites - an early bloomer in my Zone 5 garden. Its buds begin poking out of the ground in early December, and depending on the severity of the winter, will open in February or March.

This hellebore is an unusual plant from the esteemed Yokoyama Nursery in Japan, a difficult to produce hybrid between H. niger and H. x hybridus.

Each plant produces a beautiful bouquet of pure white, outward-facing flowers that last for months, turning a soft light green as they age. A lovely sight!

Astilbe Plumes Grace Shady Retreats

One of the first gardens that I created upon moving into my house was a circular shade bed at the entry to my property. A garden novice at the time, I researched appropriate plants and developed a garden of hostas, astilbes, cinnamon ferns and fringed bleeding hearts. Almost 20 years later, those same carefree plants provide a beautiful annual display, with the pink, red and white astilbes claiming the spotlight in June and July.

 Astilbes, with their elegant feathery plumes of flowers and delicate ferny foliage are native to Asia, and were first introduced to Europe in the late 1800s. Initially, astilbes were grown for forcing and used as potted plants indoors, so early hybridization focused on producing dwarf, floriferous plants. Almost every hybrid astilbe can be traced back to Georg Arends, a nurseryman from northern Germany who started crossing the white japonica species from Japan and the pink davidii species from China to produce most of 180+ hybrid astilbes in the marketplace today. One hundred years later, Arends Nursery, now run by Georg’s granddaughter, continues to introduce new cultivars. Astilbes now range in size from 8” to 48”, blooming times range from late spring to August, and colors include peaches, pinks, reds, whites, purples and lavenders.

 Astilbes bring a graceful, feathery look to the shady perennial garden. They are beautiful both as specimen plants and as mass plantings. Their fine lacy leaves look stunning juxtaposed against the bold textures of hosta, bergenia, ligularia or European ginger. The glossy foliage and soft colors also complement painted ferns and purple heucheras. Given the huge range of cultivars, a long season of bloom can be achieved in the garden. For early to mid-season, 24” tall plants, you can choose ‘Deutschland’ (white), ‘Rhineland’ (pink), ‘Bremen’ (deep pink), or ‘Fanal’ (garnet red). For mid-season bloom, 24” tall, choose ‘Amethyst’ (magenta), ‘Erika’ (pink), ‘Federsee’ (carmine), or ‘Avalanche’ (white). For the late season, there are the short (8-12” tall) varieties for the front of the border, such as ‘Pumilla’ (lilac) and ‘Sprite’ (pink) and the tall (4-5’) varieties for the back of the border such as ‘Taquetti Superba’ (lilac) and ‘Purperkurze’  (reddish purple).

Pest free and deer-resistant, hardy in zones 3-6, astilbes perform well in shady New England gardens, preferring acidic, moist, well-drained soil. In nature, they grow along stream banks in partial shade, so supplemental irrigation is essential during the dry heat of summer. When planting, be sure to work leaf compost, aged manure and peat moss into the soil and mulch with shredded leaves or bark. The mulch helps to conserve moisture and protects the crowns from heaving out of the ground in late winter.

Astilbes are heavy feeders and require high-nitrogen fertilization in spring or fall from a top dressing of composted manure or commercial fertilizers. Some astilbe growers recommend a general purpose lawn fertilizer (20-10-10) applied in early October since the plants grow steadily until frost and form their flower buds in autumn for the next year’s flowers. Deadheading is not required since it will not induce more blooms and the dried seedheads extend the seasonal interest of the plants. To ensure vigorous growth and flowering, astilbes should also be divided every three years in early spring or late summer. To divide, dig up the clump and saw it apart into several sections using an old pruning saw. 

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Geraniums: Delicate Beauty for the Perennial Garden

During a recent garden tour, I pointed out a clump of beautiful hardy geraniums to my friend, and got the usual confused look. Upon hearing the term ‘hardy geraniums’, most people look for Pelargoniums, whose big, bright blooms adorn millions of flower boxes and porch planters. The term ‘hardy geranium’ however, refers to a genus of delicate mounding perennial flowers ranging in color from cornflower blues to soft pinks, mauves, purples and  deep maroons. Also called “cranesbills” for the shape of their seedpods, hardy geraniums have flowers and foliage that are smaller and finer than those of pelargoniums, and reward the gardener by returning reliably and blooming profusely year after year.

I grow only six of the 400 species of hardy geraniums that have been identified. The plants are perfectly adapted to Massachusetts gardens, thriving in zones 4-8. Most form low, dense mounds with small cup-shaped flowers that float above the foliage on thin stems, attracting bees and butterflies. The translucent flower petals look particularly beautiful when backlit. While all species exhibit five-petaled, symmetrical flowers and finely divided palmate leaves, some have contrasting splotches or veining. Even when not in bloom, hardy geraniums add beauty to the garden from spring through fall with their leaf shapes color variations.

Hardy geraniums are extremely flexible plants, and whether you are looking to fill a dry, sunny spot, an area with part shade or a groundcover for the woodland garden, you will find a geranium that will suit your situation. I love to use Geranium sanguineum, also known as Bloody Cranesbill, in place of annuals at the front of a border. The plant forms a low (8”), wide mound with a profusion of magenta flowers light up the garden all summer long. In my garden it is gorgeous combined with purple heuchera, lamb’s ears, ‘Blue Star’ juniper and bearded irises.

For those that love masses of true blue, billowy flowers, there are two wonderful geranium varieties: ‘Johnson’s Blue’ and ‘Rozanne’. ‘Johnson’s Blue’ forms 18” mounds of cornflower blue flowers that grace my perennial bed for the month of June. ‘Rozanne’, awarded the title of  “2008 Perennial Plant of the Year”, is  taller with 2.5 inch violet-blue flowers that bloom all summer, and deep green foliage lightly marbled with chartreuse. I fell in love with it when I saw the “Rozanne River” in the Bressingham Garden at Elm Bank.

I recently acquired my first Geranium phaeum, also known as Mourning Widow or Dusky Cranesbill from the Cotton Arbo-retum in Winchester, Mass. Geranium phaeum is one of the taller species, up to 32” in bloom, with purplish brown spots on its leaves and deep maroon, almost purplish black flowers. This geranium can be grown in dry shade and combines superbly with chartreuse hostas and hanoke grass.

Although it is difficult to chose a favorite geranium species, my favorite is Geranium macrorhizum (Bigroot geranium) with its bright pink flowers in early spring, scented foliage which turns a bright scarlett in autumn, and its tolerance of dry, shady areas. I am partial to any plant that survives under my massive maple trees and adds so much beauty to such an inhospitable site.

Hardy geraniums require little care once established. They prefer moderately rich soil, and have no significant pests or diseases. I shear my plants back to their basal foliage once in mid-summer to encourage new leaf growth and reblooming. (The only exception to this is Geranium macrorhizum, which can be deadheaded and needs no shearing.) Geraniums live longer if divided every 3-5 years, and your friends will be happy to receive divisions of these wonderful plants for their own gardens.

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Bleeding Heart: An Old-fashioned Charmer

One of the most well-known and well-loved of the spring ephemerals is the old-fashioned Bleeding Heart, a graceful ornamental with rose-pink, nodding, heart-shaped flowers hanging off of arching stems. Bleeding Heart’s unique blooms delight children, and the plant’s elegant appearance enhances cottage gardens and shady retreats.

Bleeding Hearts (Dicentra spectabilis) are native to northern China and Japan, and were discovered and brought to England by a plant explorer of the Royal Horticultural Society in 1846.  The name Dicentra was derived from the Greek dis (“twice”) and kentron (a “spur”), in reference to the two hooks on each bloom, and spectabilis refers to the plant’s “showy” or “spectacular” appearance.

Although classified as shade plants, Bleeding Hearts grow best in light shade to full sun in New England. They thrive in humus-rich, well-drained soil, and will rot of the soil remains too wet. The plants grow in loose clumps, 3 feet tall and 4 feet wide. The reddish new foliage emerges from the ground in early spring and forms into powdery green leaves on fleshy stems. Bleeding Hearts flower in early May to mid summer, with each stalk bearing up to 15 individual flowers. The plants go dormant in mid to late summer and the yellowing foliage can be cut back hard at that time. The stems can be pulled out and discarded once they die back completely. Bleeding Hearts can be divided in spring or after they die back in late summer, but care must be taken with their brittle roots.

With their graceful foliage and heart-shaped flowers, Bleeding Hearts make a spectacular show in the May garden with tulips and forget-me-nots, sweet woodruff and lily of the valley at their feet. Since the foliage dies back in midsummer, I have planted mine in areas where other perennials will fill in and obscure the yellowing foliage – in back of hostas, hardy geraniums and astilbe, which come out later in the spring to fill in as the Bleeding Heart declines.

In addition to the common Bleeding Heart, there are several other noteworthy varieties including the all-white Dicentra spectabilis ‘Alba’ and the cherry-red ‘Valentine” with its ferny gray-green foliage. A real show-stopper is the recently introduced ‘Gold Heart’ with its bright yellow foliage and rose-pink flowers. Its long-lasting foliage virtually glows in the garden. Fringed Bleeding Heart (Dicentra eximia) is a beautiful choice for the woodland garden, with its ferny foliage, smaller size (about 12” high) and petite flowers. Though less striking than the spectabilis cultivar, eximia blooms longer, retains its foliage throughout the growing season and is available in pink, white or the new red ‘Burning Hearts’.

With their heart-shaped flowers, Bleeding Hearts are a favorite with children. My kids loved to pick them and drape the florets over their ears as earrings, and Bleeding Heart  flowers always graced the table for my Mother’s Day breakfast. There is an old children’s story told about the flowers that goes something like this:

The story of the bleeding heart

Once upon a time there was a prince that loved a princess who took no notice of him. To get the princess's attention and prove his love, he brought her amazing gifts from far and wide. One day he came across two magical pink bunnies and offered them both to the princess. (Storyteller pulls off the two outer pink petals and sets each on it sides to show the animals.)

The princess was unmoved by the rabbits so, he tried again and presented her with beautiful dangly earrings. (The two inner white petals are separated and held up next to the storyteller’s ears for display.)

 Still, the princess paid him no attention. The prince was so distraught over being spurned that he took a dagger and stabbed himself. (The remaining center of the flower is shaped like an outline of a heart with a line down the center. The heart is held up, the dagger-like line is removed, and the storyteller plunges the "knife" through the heart's center.)

 The princess, realizing too late that she did love the prince, cried out, "My heart shall bleed for my prince forever more!" and her heart bleeds to this day. 

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Try Tiarella in Your Shade Garden

In May, the blooms of Tiarella carpet the woodland floor with a layer of foamy haze. The fuzzy flowers are held like little bottle brushes above green leaves that often are centrally marked with maroon. Until recently, Tiarella was only grown in home gardens that were devoted to woodland plants. Now, thanks to the work of plant hybridizers and a wealth of new cultivars, Tiarella has moved into the mainstream as a shade garden perennial.

Tiarella, also known as foamflower, is a deer-resistant wildflower that is native to eastern North America and Asia. Hardy in Zones 3-9, it grows in deciduous woodlands and mountain terrains. It has attractive, low-growing, semi-evergreen foliage. Its leaves are heart-shaped or deeply lobed and are often dramatically patterned. In winter, the leaves darken to red and flatten to the ground. It produces flowers on leafless stems that can range in height from six to fifteen inches. Flowers can be white or suffused with pink.

Roughly speaking, Tiarella can be divided into two types: ground cover and clump-forming. Tiarella cordifolia var. cordifolia is a ground cover that spreads fairly quickly by stolons or runners. It is a good naturalizer. The stolons produce plant offsets that take root and bloom in their second year. Tiarella 'Brandywine' is a cultivar with slightly lobed, hairy leaves with a central maroon splotch. It produces eight-inch tall, graceful white flower spikes that last for weeks. In my garden, it is a well-behaved ground cover that mixes with variegated Solomon's Seal  (Polygonatum odoratum 'Variegatum'), 'Purple Lance' astilbe (Astilbe chinensis 'Purple Lance'), Hosta 'Abba Dabba Do', and ferns.

Tiarella cordifolia var. collina is a clump-forming type. Often, the leaves are deeply lobed and resemble the leaf of a Japanese maple. Dark purple or maroon markings along the central veins of some of the cultivars create season-long interest. The flower spikes are usually densely packed and plentiful. The flowers last for weeks and have great impact in the spring garden. I grow T. 'Spring Symphony' and T. 'Iron Butterfly' in my gardens and wouldn't be without either one. Both have semi-evergreen slightly hairy leaves that form healthy clumps that are six to eight inches tall by twelve inches wide. Both look good for the entire growing season. T. 'Spring Symphony' is extremely floriferous, with dark pink buds that open to fuzzy pink flowers. As an added bonus, it occasionally sets seed. T. 'Iron Butterfly' produces fewer flowers, but has dramatic, deeply lobed leaves with strong markings of dark purple. Both add variety and beauty to my shade gardens as they share space with hosta, epimedium, ferns, and Toad Lily (Trycertis).

Tiarella is easily grown in the home garden. It requires partial shade or full shade. It prefers humus-rich moist soil, but adapts to drier conditions once established. It is a low maintenance plant that is virtually pest-free and seldom needs dividing. Tiarella is useful in the garden as a ground cover or as a clumping perennial and looks lovely when paired with spring-flowering bulbs. It is a charming addition to the home garden. It lights up shady corners with its spikes of flowers and creates season-long interest with its intricately patterned foliage.

Tiarella can be purchased locally at numerous garden centers including Weston Nurseries and from on-line sources such as Mason Hollow Nursery www.masonhollow.com.

By Joan Butler

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Jeffersonia: A Woodland Wildflower for the Home Garden

Springtime in the woodlands of eastern North America begins slowly and ends with a crescendo of blossoms that carpet the forest floor in May. Many of the earliest wildflowers in this succession of bloom can be effective and adaptable additions to the home shade garden. One such wildflower is our native twinleaf, Jeffersonia diphylla. Its flowers are fragile and fleeting, lasting only a couple of days, but they are a sure sign of spring. The delicate floral beauty and intriguing leaf shape of Jeffersonia make it a desirable plant for gardeners who want to try something new in their shade gardens.

Jeffersonia diphylla is a clump-forming woodland perennial that is hardy in Zones 5-7. Its white, daisy-like flowers are one inch in diameter and cup-shaped. They are borne individually atop eight-inch, wiry, leafless stems. The flowers are followed by unusual pear-shaped seed pods with hinged lids. As the pod stalks elongate, the leaf stems also grow, and the plant ultimately reaches a height of eighteen inches. Twinleaf derives its common name from the shape of its deeply divided leaves. Each leaf is about five inches wide by six inches long and is divided into two nearly separate halves, like a mirror image. It resembles a butterfly that flutters atop its slender stem. When the leaves first emerge from the soil they are a unique, rich coppery red. The copper color slowly fades, and the foliage takes on a chalky, blue-green hue. Twinleaf makes a significant contribution as a ground cover in the woodland and home garden, adding bold texture and unusual form.

The only other species of twinleaf in the world occurs in the woodlands of eastern Asia. This species, Jeffersonia dubia, is similar in many respects to its American counterpart. Its flowers, however, last up to two weeks and are a remarkable soft lavender-blue. The plants are about six inches in bloom, with the leaf stalks ultimately growing to twelve inches. The leaves of J. dubia are not as deeply divided as our native twinleaf and, although lovely, have a less pronounced effect as a ground cover.

Horticulturalist William Bartram named Jeffersonia in honor of his friend, Thomas Jefferson. The bloom time of Jeffersonia roughly coincides with the President's April 13tthbirthday. Although it is  considered poisonous, twinleaf has been used throughout history as a medicine. Native Americans used it in poultices and infusions to treat a variety of ailments. Traditional Chinese medicine used it as a treatment for the stomach and fevers.

Jeffersonia is notoriously difficult to propagate by division since it grows from a very dense crown. Happily, it grows easily from seed. I grow both species in my gardens and have found that J. dubia reseeds itself more energetically than our native twinleaf. I move some of the tiny seedlings to new locations or grow them on in nursery beds. J. diphylla spreads less readily and new seedlings take years to produce flowers, but, for me, the eventual blooms are more momentous due to the wait.

As is the case with most woodland wildflowers, Jeffersonia is most successful in home garden situations that mimic its native habitat: deciduous woodlands with rich, moist, calciferous soils. In the home garden, it requires shade, but adapts very well to drier conditions once established and will thrive in soils within the normal range of acidity. No garden should be without the delicate beauty of its spring blossoms and the presence of its unusual and aptly named leaves.  You can purchase twinleaf locally from Garden in the Woods in Framingham and from online sources such as Mason Hollow Nursery, www.masonhollow.com.

By Joan Butler

The Ephemeral Beauty of Bloodroot

Spring is the season we all await impatiently. During this time of year, I can be found scouting my gardens nearly every day, searching for the slightest hint of new green growth pushing up through the bare earth. Already, there are crocuses and snowdrops in bloom in my gardens and in just a few short weeks, the early spring ephemerals will be in full force with their delicate and fleeting beauty. Bloodroot is one of the first of these early bloomers and it is also one of the loveliest. Pure white, upward-facing flowers and thick, grayish-green leaves grace this beautiful, yet rugged, woodland perennial.

Bloodroot (Sanguinaria canadensis) derives its name from the dark red sap contained in its foliage and rhizomes. This sap makes Bloodroot unpalatable to deer. It is native to eastern North America, from Canada south to Texas and Florida, and is hardy to Zone 3. In its natural habitat, it thrives in deciduous woodlands, where spring sunshine is followed by dappled summer shade. Although it prefers rich, moist soil high in organic matter, it can adapt to a wide range of soil and moisture conditions, making it ideal for shady spots in the suburban garden. It does not tolerate soggy or extremely dry conditions. It spreads by fleshy, orange rhizomes that lie one to three inches below the soil surface. It also spreads by seed and can form extensive swaths in the woodland. Bloodroot is one of the many woodland wildflowers whose seeds are spread by ants, a process called myremecochory. Ants gather the seeds and store them in underground nests where they feed upon a fleshy appendage attached to each seed. In this way, the ants essentially plant the seeds in an environment where they stay protected until they germinate the following spring.

When Bloodroot first emerges from the ground, each flower bud is wrapped tightly by a single leaf. As the leaf unfurls, it folds in half and gently clasps the flower stem. The flower stem pushes upward past the leaves, and the bud opens to reveal snow-white petals on flowers that are two inches wide. Individual flowers drop their petals within a few days of fertilization, but the leaves continue to expand to five to eight inches, creating a unique, bold-textured ground cover of deeply lobed foliage that lasts well into autumn. Bloodroot is easy to grow by planting divisions of its fleshy rhizomes in spring. It will also spread in the home garden by self-seeding.

Two noteworthy forms of our native Bloodroot are the single-flowered pink form and the double-flowered white form (S. 'Multiplex'). The flowers of S. 'Multiplex' resemble miniature water lilies that seem to float above the foliage. The flowers are sterile, longer-lasting and stunning. The pink form has deep pink buds that open to light pink flowers. Plus, the stems of the leaves and flowers are a rich, dark pink. Both forms prefer shaded, woodland conditions and both perform well in the home garden.

In my gardens, a sizable patch of Bloodroot grows between a large-leaf rhododendron and a variegated dogwood (Cornus kousa 'Wolf's Eye'). I can see the single white flowers of the Bloodroot from my living room window. I know they won't last long, so I make sure I get out there on a sunny day to enjoy their simple elegance. In summer, the large, lobed foliage plays nicely with hosta, pulmonaria and astilbe. The double-flowered form of Bloodroot grows beneath a large cedar, where its exquisite flowers take my breath away. Its summer foliage is particularly large and holds its own with a large clump of  'Brilliance' Autumn Fern (Dryopteris erythrosora 'Brilliance') and large-leaved hosta (H. 'Deep Blue Sea' and H. 'Three Sisters'). I am still on the look-out for my next acquisition: the pink-flowered form. I know I can make room for it, somewhere.

Bloodroot can be purchased from online sources such as Arrowhead Alpines, www.arrowhead-alpines.com. It is also available locally at Garden in the Woods, the headquarters of the New England Wildflower Society, in Framingham. Garden in the Woods opens this year on April 15, a date that coincides with the time that many spring ephemerals, including Bloodroot, have emerged from winter dormancy and carpet the woodlands with their elegant beauty.

By Joan Butler

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