Author: Russell Stafford

Hortiholic and plant evangelist, Russell Stafford, transplanted his first perennial at age 7 and thereby began a lifelong plant addiction. He is the founder and custodian of Odyssey Bulbs (and Odyssey Perennials), an online nursery specializing in cool and uncommon plants. Russell also works as a horticultural consultant, freelance writer (Horticulture and The American Gardener magazines), and garden editor. He formerly served as Curator and Head of Horticulture at Fernwood Botanic Garden in Niles, Michigan and as the Horticultural Program Coordinator at the Center for Plant Conservation, then located at the Arnold Arboretum in Jamaica Plain, Massachusetts. His academic degrees include a masters in forest science from Harvard University.

The Best Landscape Hydrangeas

Hydrangeas, circa 1970, were a bit of a bore, represented by a few stodgy standbys such as the Victorian, mophead-flowered PeeGee hydrangea (Hydrangea paniculata ‘Grandiflora’). Today, however, they’re the epitome of horticultural cool, with numerous new and exciting varieties to choose from.

Panicle Hydrangea Hybrids

Hydrangea paniculata 'Tardiva' — *Hydrangea paniculata* ‘Tardiva’

Witness, for example, what’s happening in the world of panicle hydrangea (Hydrangea paniculata). Where once there was only ‘Grandiflora’, there now are dozens of seductive cultivars of this East Asian native, in a variety of shapes and colors. Many bear lacy, white steeples in the manner of ‘Tardiva’, an old (and – until recently—neglected) variety that is still unsurpassed for its showy blooms that peak in August and September, weeks later than most other paniculatas. Comprising both large, sterile florets and small, fertile florets, the blossoms possess an airy elegance that eludes ‘Grandiflora’ and other sterile-flowered, mophead forms. Numerous other excellent ‘Tardiva’ types – such as ‘Kyushu’ and ‘Chantilly Lace’ – have recently entered the scene. Most flower in midsummer.

Some recent cultivars come in hues and sizes that are new to the paniculata tribe. The lacy spires of ‘Pink Diamond’ and the early-summer-blooming ‘Quick Fire’ gradually evolve from white to dark pink, passing through a beguiling bicolored phase along the way. In contrast, ‘Limelight’ deepens its snowball blooms to an astonishing chartreuse-green that glows most brightly in partial shade. The dwarf cultivar ‘Little Lime’ does similar things on a smaller scale (4 to 5 feet tall rather than the typical 8 to 12). It exemplifies another welcome paniculata trend: compact cultivars that fit nicely in smaller gardens. White-flowered examples include ‘Little Lamb’ and ‘Bobo’.
Even the stodgy old PeeGee hydrangea has undergone a makeover, with the introduction of several cultivars (including ‘Unique and ‘Webb’s’) that outdo ‘Grandiflora’ in the size and showiness of their snowball inflorescences.
Most paniculata cultivars respond well to severe pruning in early spring, which restricts their height, increases their inflorescence size, and slightly delays their bloom. In whatever form, they’re among the hardiest and most adaptable ornamental shrubs, thriving in full to partial sun from USDA hardiness zones 3 to 8.

Big Leaf Hydrangea Hybrids

Hydrangea macrophylla 'Harlequin' — Hydrangea macrophylla ‘Harlequin’ only performs well in USDA zones 6b to 9. (photo by Jessie Keith)

Cold-hardiness is much more of an issue for undoubtedly the most popular hydrangea species. Prized in USDA zones 6b to 9 for its reliable summer display of showy blue, pink, or white blossoms, bigleaf hydrangea (Hydrangea macrophylla) has long been the despair of gardeners in zones 5 to 6a. There, it typically dies to the ground in winter, resulting in a disappointing summer display of lush foliage and few to no blooms. Breeders are hard at work, however, on a new generation of “re-blooming” cultivars that flower on the current year’s growth. Several have made it to market, including the much-hyped blue-flowered mophead ‘Endless Summer’.

To date, none of these ballyhooed newcomers are consistent performers in zones 4 and 5, alas. But for gardeners in milder zones, these and other recent introductions make for a larger selection of Hydrangea macrophylla cultivars than ever before.

Several other highly ornamental East Asian hydrangeas (such as Hydrangea serrata, H. aspera, and H. heteromalla) are increasingly available from American nurseries. All are well worth trying, where hardy.

Smooth Hydrangea Hybrids

Ivory hydrangeas — Most new sooth hydrangeas have attractive globes of ivory, sterile florets.

Two eastern North American species have also seen a significant fashion upgrade in the past few decades. Fifty years ago, smooth hydrangea (Hydrangea arborescens) meant one thing: ‘Grandiflora’, commonly known as Hills of Snow. A classic pass-along plant, this suckering, 4-foot shrub formed many a backyard thicket, topped in summer by mildly ornamental, loosely structured, 6-inch globes of dull-white sterile florets.

Today, ‘Grandiflora’ has numerous successors, most operating on a grander (and floppier) scale. Their queen mother is the ubiquitous ‘Annabelle’, whose foot-wide midsummer domes are notorious for toppling. Her several imitators, such as ‘Incrediball’, also topple, as does the recently introduced pink-flowered snowball, ‘Invincibelle Spirit’.

Gardeners looking for a sturdier (and more charming) arborescens variety can opt for the ravishing ‘Mary Nell’, which bears showy, stylish, snow-white lacecaps on stout 4-foot stems. Another wonderful option is Hydrangea arborescens ssp. radiata, whose leaves are often lined underneath with a luminous silver-white felting that flashes in the breeze.

Oakleaf Hydrangea Hybrids

Hydrangea quercifolia 'Alice' — Hydrangea quercifolia ‘Alice’ (photo by Jessie Keith)

Oakleaf hydrangea (Hydrangea quercifolia) is yet another eastern U.S. native that offers many more delicious possibilities than ever before, including several pink-flowered and double-flowered varieties. The best (such as ‘Snow Queen’) produce showy spires on strong flop-resistant stems furnished with bold, deeply lobed leaves that turn burgundy-red in fall.

Full-size selections grow to 7 or more feet, but gardeners with more limited space can now choose from a bevy of excellent compact-growing cultivars including ‘Munchkin’, ‘PeeWee’, and Sikes Dwarf’. Of particular note is ‘Ruby Slippers’, a compact variety whose flowers age from the usual white to a much less typical deep pink.

Hydrangeas grow well in a variety of partial shade and sun locations, so long as they have fertile garden soil that drains well. Amending yearly with organic amendments, such as Fafard Garden Mature Blend, and top dressing with leaf mulch will help support plants and encourage best growth.

Hydrangea quercifolia 'Sikes' Dwarf' — Hydrangea quercifolia ‘Sikes’ Dwarf’

Gardens with a Silver Lining: Silver-Leaved Plants

Eryngium with honeybee — A honeybee feeds on the silvery blue flowers of Eryngium. (photo by Jessie Keith)

A silver- (or gray- or blue-) leaved plant is like a refreshing splash of moonlight in the garden. Its ghostly foliage deepens and enriches the pinks and blues and whites of phlox, campanulas, delphiniums, and other neighboring plants, and enlivens the varied hues of their leaves. Used individually, silver-leaved plants are gleaming exclamation points in a sea of green. Massed, they form a silvery sea of their own, altering the whole feel of the landscape.

Artemisia 'Powis Castle' — Artemisia ‘Powis Castle’ (photo by Jessie Keith)

Most silver-leaved plants come from dry, sunny habitats, and their presence suggests something Mediterranean or alpine. They look right at home among stones, whether in a rock garden or a formal terrace. Many are also fuzzy, adding to the tactile texture of a planting. They invite viewers in closer, for a touch.

Buddleja alternifolia — *Buddleja* alternifolia (photo by Jessie Keith)

Among the most valuable of the silvery set are the few that favor shade. Two species of hosta are undoubtedly the queens of this tribe. Hosta sieboldiana has contributed numerous outstanding varieties and hybrids, including some of the most magnificent plants for shady gardens. The prototypical sieboldiana hybrid, ‘Elegans’, brandishes foot-wide, frosty, blue-gray leaves, creased with deep, curving veins. Where happy, it matures into a majestic, 3-foot tall specimen. Several even more immense blue-leaved hostas have followed in its wake, including ‘Blue Mammoth’ and ‘Blue Angel’. All produce steeples of lavender or white flowers in late spring and early summer.

On a smaller scale (but literally in a similar vein) are the numerous hybrids of Hosta tokudama and its relatives, characterized by heavily veined and puckered, steely-blue leaves. Among the most popular is ‘Blue Cadet’, which makes foot-tall hummocks of pointed leaves, topped in late summer by pale lavender flowers. ‘Love Pat’ bears cupped, puckered leaves in 2-foot mounds, punctuated by early-summer spikes of pale lilac blooms. All blue-leaved hostas appreciate a moist, humus-rich soil (amend sandy or heavy soils with a good compost such as Fafard® Premium Natural & Organic Compost).

Silvery Dianthus (photo by Jessie Keith)

A few ferns contribute silver to shady areas of the garden (and pair beautifully with hostas). The classic example is Athyrium niponicum var. pictum, whose feathery, 2-foot fronds are brushed with pewter. Their maroon-flushed stems complete the picture.

Gray, blue, and silver foliage is much easier to come by in sun. The extensive list of sun-loving perennials in this color range includes the following.

Selections and hybrids of the yarrow hybrid Achillea x taygetea. Plates of yellow flowers arise from ferny, pungently scented foliage in early summer. Perennial favorite ‘Moonshine’ bears lemon-yellow flowers on 2-foot stems. Somewhat brassier blooms crown the 3-foot stems of ‘Coronation Gold’.
Several species and hybrids of Artemisia. Cultivars of Artemisia ludoviciana such as ‘Silver King’ and ‘Silver Queen’ spread rapidly into expansive, 2- to 3-foot-tall clumps of finely textured, silver-gray foliage. In contrast, the justly popular ‘Silver Mound’ forms well-behaved, one-foot domes of silky, filigreed leaves. It prefers a soil that’s not too moist or fertile, melting out in unfavorable sites (particularly in hot humid weather).
Any number of Dianthus, such as cottage pink (Dianthus x allwoodii), cheddar pink (Dianthus gratianopolitanus), and grass pink (Dianthus plumarius). All are prized for their early-summer bounty of fringed, red to white, clove-scented flowers, presented above low, fine cushions of narrow, waxy, dusted leaves.
Sea hollies (Eryngium spp.). Bristling clumps of jagged, lobed, often spiny leaves give rise to thimble-like clusters of blue to silver flowers ringed by bold, spiky collars of pointed bracts. The architectural biennial Eryngium giganteum makes a striking subject for cottage gardens and other areas where it can self sow. Most sea hollies bloom in early to mid-summer.
Russian sage (Perovskia atriplicifolia and hybrids), a shrubby perennial producing tall, hazy spikes of lavender flowers in summer on upright woody stems with small felted leaves.
Several salvias, most notably the short-lived perennial Salvia argentea. Its large rounded basal leaves are thickly (and irresistibly) felted with silver.
The long-time fuzzy favorite Stachys byzantina, affectionately (and appropriately) known as lamb’s ear. Grown primarily for its mats of felted, silvery, tongue-shaped leaves, it comes in various sizes and guises, including a cultivar (‘Silver Carpet’) that lacks the usual furry-stemmed spikes of purplish flowers.

Perovskia atriplicifolia 'Little Spire' (photo by Jessie Keith) — Perovskia atriplicifolia ‘Little Spire’ (photo by Jessie Keith)

Among the many notable silver-leaved shrubs and trees are lead plant (Amorpha canescens), butterfly bush (Buddleia spp.), silver-leaf hydrangea (Hydrangea radiata), creeping willow (Salix repens var. argentea), dusty zenobia (Zenobia pulverulenta), silver fir (Abies concolor), blue Atlas cedar (Cedrus atlantica ‘Glauca’), willow-leaf pear (Pyrus salicifolia), and white spruce (Picea engelmannii). There’s something in silver for every garden.

Border Veggies: Edible Ornamental Bulbs

Purple chive flowers — Chives are pretty in the garden and on the plate. Their flowers are edible, too! (photo by Jessie Keith)

Edible ornamental bulbs (or is it ornamental edible plants?) are wonderful garden playthings. As welcome in a recipe as in a mixed border, they appeal both to our love of beauty and to our utilitarian, subsistence-gardening roots.

No plants go more to the root of edible gardening than the ones we know as flower bulbs (although most are not roots or bulbs in the strict botanical sense). From the moment humans discovered that many plants grow from nutrient-rich underground storage organs, we’ve been scratching the dirt harvesting and cultivating that subterranean bounty. At the same time, we’ve been captivated and seduced by the colorful things that many bulbs do above-ground. They’re a feast for the eyes and the palate.

Siberian native *Allium obliquum* has edible bulbs and yellow, early-summer flowers.

Several other alliums make more handsome garden subjects. Chives (Allium schoenoprasum) has long been treasured for its attractive clumps of hollow, quill-like leaves and its late spring to early summer globes of purple to white flowers. The somewhat similar (but much later-blooming) Allium chinense is a favorite potherb in its native East Asia, where it’s garnered a host of common names, including rakkyo and Jiao Tou. Also from East Asia, Allium tuberosum (commonly known as garlic chives) bears larger, looser heads of white flowers on 18-inch stems in late summer. The leaves and flowers make tasty and eye-catching embellishments for salads and other summery repasts. Whether eaten or not, garlic chive flowers should be deadheaded to prevent the prolific self-sowing for which the species is notorious. All the above thrive in sun and fertile, friable soil (amend heavy or sandy soil with Fafard® Premium Natural & Organic Compost Blend).

Crous sativus 'Cashmerianus' — Greek native *Crocus cartwrightianus* bears exceptional saffron.

Shadier niches provide ideal habitat for two woodland onions traditionally harvested for their broad, piquant, short-lived leaves. The greens and bulbs of bear’s garlic (Allium ursinum) have played a part in European and North Asian diets for many centuries and still find their way onto menus (especially in chic restaurants). In eastern North America, the tasty, trendy woodland onion is Allum tricoccum, subject of traditional “ramps” celebrations over much of its native range. Over-collecting has rendered it relatively scarce in the wild, but ramps (as well as bear’s garlic) is usually prolific in the garden, spreading vigorously into large leafy clumps. An ideal way to slow it down in cultivation is to sacrifice a few leaves to a springtime omelet, stir-fry, soup, or other morsels. Its flowers are also edible; they appear on 15-inch scapes in early summer, after the foliage has withered. Bear’s garlic produces similar (but slightly showier) flowers in spring, while still in leaf. (Click here to read more about growing ramps at home.)

Springtime greens of a different sort are the stuff of Ornithogalum pyrenaicum. This high-rise star-of-Bethlehem is famous (at least in the neighborhood of Bath, England) for its succulent immature flower stalks that resemble asparagus spears. Formerly gathered from the wild and sold in markets in its namesake town, Bath asparagus is enjoying something of a culinary revival as a cultivated plant in Southwest England and elsewhere. Unharvested stalks mature into 30-inch spires of starry white flowers, which themselves are well worth a place in mixed borders and cottage gardens. Native to Southern Europe, Bath asparagus was likely introduced to England by Roman occupiers (who apparently also had good taste in ornithogalums).

Southern Europe is also the home of what is almost certainly the most valuable edible bulb: saffron. Several thousand Crocus sativus flowers are required to produce one hand-harvested ounce of this precious seasoning, which is literally worth its weight in gold. Most of the world’s saffron crop comes from Iran, but it’s been cultivated for centuries in many other areas including Pennsylvania’s Amish country. It is not known in the wild.

Bath asparagus in full bloom. (Photo by Garrytowns)

Crocus sativus has three sets of chromosomes and is unable to produce seed, suggesting that it probably originated as a hybrid or mutation of another crocus species (Greek native Crocus cartwrightianus is the leading candidate). Several other close relatives (including C. pallasii and C. oreocreticus) of saffron crocus also occur in Southeast Europe, all of them carrying the characteristic fragrant, orange-red stigmas at the centers of their purple to lavender, mid-autumn blooms. Crocus sativus and its relatives prosper in full sun and rich fertile soil in USDA Hardiness Zones 6 to 9. They’re perfect for planting near an entryway, where their tasty stigmas can be readily harvested for that next loaf of saffron bread.

Edible bulbs offer possibilities for all sorts and sizes of ornamental plantings, from a container of herbs to a permaculture landscape. Dig in!

South African Bulbs for Indoor Growing

*Lachenalia aloides* var. *quadricolor* is beautiful and flamboyant.

Most Cape bulbs follow the seasonal rhythms of their native land, beginning to push leaves in late summer or fall (whether watered or not), and flowering at their appointed time in late fall, winter, or early spring. Their flowers also tend to share a certain likeness, with many species bearing heads of narrow, tubular, brightly colored blooms on stout scapes – the better to attract and accommodate the long-billed, brilliantly hued sunbirds that pollinate them.

Cape Hyacinth

Veltheimia bracteata (commonly known as forest lily or cape hyacinth) beautifully exemplifies these Cape bulb traits. Handsome in their own right, the lustrous, wavy-edged, strap-shaped leaves (with perky wavy-edged margins) emerge from fleshy, tennis-ball-sized bulbs in late summer. In midwinter, red-hot-poker heads of tubular pink flowers develop on fleshy purple-flushed scapes that slowly elongate to 18 inches or so. Flowering peaks about Valentine’s Day, but continues for several weeks before and after. An almost indestructible house plant, Veltheimia bracteata thrives in bright indirect light, relatively tight quarters, and a porous potting mix (such as Fafard® Professional Potting Mix with RESiLIENCE). Shallow planting (with the “shoulders” exposed) suits the bulbs well. Plants prefer a dry, shady summer rest after the foliage begins to flag in late spring.

Lachenalia

Showy, tubular blooms also make a frequent appearance in the genus Lachenalia. Lachenalia aloides is perhaps the most flamboyant, flaunting proportionately large golden-orange blooms that nod on 10-inch scapes in mid- to late winter. Some forms of this species take the flamboyance one step further, adding horizontal bands of crimson, yellow, purple, and green to the floral color scheme. Variety quadricolor is one such dazzler, with orange-based blooms that shade to yellow at their midriffs and purple-red at their tips. Flowers of the cultivar ‘Nelsonii’ have brilliant red buds that turn lemon-yellow with lime-green tips as they expand. Purple splotches ornament its stems and leaves, another characteristic of many forms of this striking species. Other highly ornamental species include Lachenalia bulbifera, with lipstick-red flowers that open around Christmas, and Lachenalia rubida, whose freckled, rose-pink, late fall blooms are the earliest in the genus. Lachenalia hybrids are also now available, most notably in the form of the African Beauty Series (including ‘Namakwa’, ‘Rupert’, and ‘Romaud’).
All of the above lachenalias prosper in containers. Shallow planting (one inch deep or so) in a porous potting mix is best, with moderate watering during the growing season. Lachenalias like it cool and sunny while in growth but should be moved to a dry, shady location when dormant.

Lachenalia fanciers often find themselves drawn to the many species that flower in less gaudy but equally seductive hues (sometimes with fragrance thrown in). The flowers of Lachenalia viridiflora, for example, are of a luminous, other-worldly turquoise-green, making for a singular late fall to early winter display. These lesser-known and lesser-grown Lachenalia species can be somewhat tricky in cultivation, but all are worth the effort.

Haemanthus

Not all Cape bulbs fit the tubular mold. Haemanthus albiflos is a striking example, brandishing white, up-facing shaving-brush flowers on short fleshy stems in fall or early winter. The leathery, tongue-shaped, evergreen leaves are also attractive. This drought-tolerant species is practically indestructible if shallowly planted in a porous potting mix in a bright but not too warm location.

Oxalis

North American gardeners tend to think of Oxalis species (commonly known as wood sorrel) as horticultural thugs. Many Cape Oxalis, however, are of a far more rarified (and less invasive) plane, featuring jewel-like flowers and lush, ornamental foliage. Oxalis purpurea deserves a place on every cool sunny windowsill in need of winter color. Its numerous varieties flower in a rainbow of colors, from white to rose-pink to raspberry-red to lemon-yellow, and its rich green “shamrock” leaves are sometimes suffused or blotched with contrasting colors. The cultivar ‘Ken Aslet’ – distinguished by felted silvery leaves and brilliant yellow flowers – is usually sold as this species (but probably belongs under Oxalis melanosticta). Also invaluable for winter bloom are lilac-flowered, fuzzy-leaved Oxalis hirta; candy-striped Oxalis versicolor (with white, carmine-edged petals); and numerous other Cape Oxalis. All flourish in a porous potting mix kept reasonably moist in winter and dry and relatively cool in summer.

Look for these and other winter-blooming Cape bulbs in mainstream and specialty plant catalogs, as well as in local greenhouses and grocery stores. A touch of South Africa can do wonders for a dreary winter’s day.

Trees with Beautiful Winter Bark

A number of hardy tree species possess bark that is eye-catchingly handsome, particularly in winter, when most everything else in the garden is dressed in frostbitten drab. Such trees are essential for bringing defining structure and color and texture to the winter landscape.

Maples

The maples have given us a number of trees that possess arresting bark, including the iconic paperbark maple (Acer griseum). In its best forms, this highly variable Chinese native slowly matures into a 25- to 35-foot, round-headed specimen with polished, flaking, cinnamon-brown bark that is especially striking when frosted with snow. The three-parted leaves assume sunset tones rather late in fall.

Paperbark maple interbreeds with another trifoliate East Asian maple (Acer nikoense), which has striking green streaked bark, to produce hybrids with finely shredded bark of a somewhat paler cinnamon-brown. A third species in the three-leaved maple tribe, three-flowered maple (Acer triflorum), has shaggily flaking, silvery- to creamy-gray bark. It, too, is a small to medium tree, perfectly sized for most residential gardens in USDA Cold Hardiness Zones 5b to 8. Sunny or lightly shaded sites work best.

Snake-bark maples constitute another group well worth growing for their colorful stems. Arguably the most beautiful is red-vein maple (Acer rufinerve). Some selections of this fast-growing, medium-sized tree have luminous lime-green bark marked with paler longitudinal fissures. Abundant, colorfully winged fruits dangle from the branches late summer and early fall. This Japanese native is closely related to our native moosewood (Acer pensylvanicum), which is sometimes represented in gardens by the red-stemmed cultivar ‘Erythrocladum’. Both do well in sun or partial shade.

Stewartias

Like the maples, the genus Stewartia is centered in temperate East Asia and eastern North America and contains several species with beautiful bark. The best known, Japanese stewartia (Stewartia pseudocamellia), bears white, camellia-like flowers in early summer, and oval leaves that go fiery in fall. Its most notable feature, however, is its multicolored bark, which exfoliates into mottled patches of gray and bronze and pinkish-tan. Other, far lesser known stewartias (including Stewartia rostrata and S. sinensis) are also beautifully mottled. Also noteworthy is Stewartia monadelpha, a relatively slight species whose bark resembles that of paperbark maple. All these stewartias are small, rather spreading trees that make good choices for sunny to partly shaded niches in modest-sized gardens. Most are hardy to USDA Zone 5b.

Lacebark Elm

Japanese Stewartia bark — Japanese stewartia

A diverse species that occurs over a wide range of Asia in a wide variety of shapes and sizes, lacebark elm (Ulmus parvifolia) has given rise to numerous cultivars, including some dwarf selections that make ideal bonsai subjects. For the garden, forms with exfoliating bark are undoubtedly the most desirable, their trunks maturing into a stewartia-like patchwork. All forms flourish in full sun, and most will weather USDA Zone 5b conditions.

Persian Ironwood

Also notable for its showy patchwork bark (and also hardy into USDA Zone 5b) is a medium-sized tree from the witch-hazel family, Persian ironwood (Parrotia persica). Typically multi-stemmed and wide-spreading, it bears leaves that resemble common witch-hazel and produces curious little early spring flowers composed of clusters of purple stamens. Fall color is often a spectacular blaze of orange, red, and smoky purple, with the brightest coloration occurring in full sun.

Amur Chokecherry

One of the best ornamental trees for sunny niches in especially chilly regions (USDA zones 3 to 6), Amur chokecherry (Prunus maackii) grows rapidly into a medium-sized tree with lustrous, shredding, tawny-orange bark that fairly glows in the winter landscape. Rounded clusters of white flowers open in spring and are followed by small black fruits. Although relatively short-lived and prone to damage from heavy wet snow and ice, it is still unsurpassed as a four-season tree for cold-climate gardens.

Peking Tree Lilac

A. nikoense x A. griseum bark — *A. nikoense* x *A. griseum*

The Peking tree lilac (Syringa pekinensis) resembles Amur chokecherry both in its exceptional cold-hardiness (USDA zones 3 to 7) and in the exfoliating, coppery bark of its finest forms (such as ‘Copper Curls’). But this variable Manchurian native offers greater longevity and clay-soil tolerance, as well as a bevy of fleecy, fragrant early-summer flowers. Typically multi-stemmed, it grows at a moderate rate to 20 to 30 feet tall, prospering in most soils in full sun.

Amur Maackia

Fafard Premium Natural & Organic Compost Blend pack

Copper-tinged bark and USDA Zone 3 hardiness are also among the virtues of another small tree from the harsh climes of Manchuria, Maackia amurensis. Amur maackia’s bark is remarkable not only for its rust-brown coloration but also for the diamond-shaped exfoliations that decorate its surface, inviting closer inspection. Upright candelabras of dull white flowers deck its branches in early summer. The pinnately compound foliage of this single-stemmed, round-crowned, leguminous tree is an attractive dark green in summer but offers little in the way of fall color. Growth is slow, even in ideal conditions (full sun and fertile, well-drained soil).

Plant one of these trees with beautiful winter bark next spring, and it will bring much-needed color and presence to the garden next winter (and for years to come). To get it off to a good start, give it a planting hole that’s about the same depth as the root ball, and three times as wide. Amend the backfilled soil with a bit of balanced fertilizer, as well as a humus-rich amendment such as Fafard Natural & Organic Compost Blend if the soil is excessively sandy or heavy.

All About Amaryllis

The bright, bold blooms of Amaryllis add to the holiday festivities. (photo by Maureen Gilmer)

Amaryllis are emblems of the winter holiday season, their bold, flamboyant flowers decorating everything from greeting cards to wrapping paper to the holiday table itself. Known botanically as Hippeastrum, they trace their origin to a number of Hippeastrum species that inhabit the anything-but-wintry forests and slopes of tropical South America. Plant hybridizers have interbred these species over the past 250 years, ultimately producing the showy-flowered, large-bulbed amaryllis hybrids that populate garden centers and bulb catalogs in fall.

Amaryllis gifts — Amaryllis, and other bulbs for forcing, can be found pre-forced or boxed for winter forcing.

Obtaining Amaryllis

Purchased amaryllis bulbs put on a lavish display with ridiculous ease. Most come from overseas growers, who have conditioned the bulbs to provide immediate gratification upon planting. Take an amaryllis bulb, half-bury it in a free-draining potting mix (such as Fafard® Natural & Organic Potting Soil with Resilience™), add water, and – voila – it happens. Plump, spear-shaped buds arise on thick fleshy stems, achieving spectacular full bloom within a few weeks after planting.

Many amaryllis are sold pre-installed in a plastic pot. More satisfactory, however, is a deep clay pot, which provides ballast to counterbalance the weight of the huge blooms. Plant the bulb with its top half exposed, to give the roots maximum growing space. Bright light and relatively cool temperatures (60 to 65 degrees F) result in stockier growth, which also discourages toppling. An east-facing windowsill is ideal.

Bringing Amaryllis to Bloom

Bringing purchased amaryllis to bloom is a cinch. Coaxing it to repeat the performance is a trickier proposition. To rebloom, the bulb needs a period of dry rest, approximating what its ancestors experience in the wild. In their native habitats in eastern Brazil and in the foothills of the Andes, most Hippeastrum species produce flowers and foliage during the spring and summer rainy season, becoming quiescent when the weather turns drier in fall and winter.

Amaryllis hybrids in cultivation require a similar wet/dry treatment. Regular watering and feeding after bloom, followed by withdrawal of water in summer, will typically trigger a new round of flowering when watering is gradually resumed in late fall. Many amaryllis fanciers move their plants to a partly shaded outdoor location after the last frost date, bringing them back inside for their dry rest period. Plants generally do best if left in their containers and repotted only when absolutely necessary (once every 4 or 5 years should do).

Amaryllis 'Dancing Queen' — Amaryllis ‘Dancing Queen’ is a pretty double form. (photo by Pam Beck)

Dutch Amaryllis

Hybrid amaryllis bloom in a variety of colors, sizes, and shapes. Best known are the large-flowered Dutch hybrids, with immense, wide-flaring, six-petaled blooms that owe much of their form and coloration to the red-flowered Bolivian native Hippeastrum leopoldii. Old-time favorites from this group include ‘Red Lion’ (introduced in 1958), pink-striped ‘Apple Blossom’ (1954), and white, crimson-edged ‘Picotee’ (1958). More recent introductions – such as velvety burgundy-maroon ‘Red Pearl’ and tangerine ‘Naranja’ – are gradually supplanting some of the old standbys. Also relatively new to the scene are a race of Dutch Hybrids that bloom in 4 to 6 weeks from planting, rather than the typical 8 to 10. These “Christmas-Flowering” amaryllis come in the customary range of whites, pinks, and reds.

Double Dutch Amaryllis

Other hybrid groups include double-flowered Dutch Hybrids (such as purple-red-striped ‘Double Record’ and pure white ‘Ice Queen’) and miniature amaryllis. The latter have the appearance of scaled-down Dutch Hybrids, bearing 3- to 4-inch (rather than 8- to 10-inch) blooms on somewhat shorter stems (10 to 16 rather than 18 to 24 inches).

Butterfly Amaryllis

Hippeastrum aficionados have many more groups of hybrids to explore, as well as the species themselves. Selections and hybrids of the butterfly amaryllis, Hippeastrum papilio, offer several takes on its curious green and maroon, asymmetrical flowers (look for ‘Grafitti’ and ‘Papilio Improved’). Hippeastrum cybister has lent its narrow-petaled, spidery form to a growing number of hybrids including ‘Chico, ‘La Paz’, and ‘Emerald’. And trumpet-flowered amaryllis such as raspberry-striped ‘Santiago’ and candy-pink ‘Estella’ – with elongated, funnel-shaped blooms – are becoming increasingly available from bulb sellers.

Amaryllis in different stages — Amaryllis bulbs at different stages of forcing. (photo by Maureen Gilmer)

Gardeners in USDA zones 7 and warmer can even try amaryllis in the garden. Hardiest of all is St. Joseph’s lily, Hippeastrum x johnsonii, whose trumpet-shaped, crimson, white-starred flowers (on 2-foot stems) have ornamented Southeast U.S. gardens since the mid-nineteenth century. So, too, have the dazzling crimson blooms of oxblood lily, Rhodophiala bifida, which look for all the world like dwarf amaryllis (indeed, the species was formerly included among the Hippeastrum). Both make wonderful subjects for gardens from the Mid-Atlantic southward, the trumpets of oxblood lily providing a late-summer echo of St. Joseph’s lily’s spring display. Dutch Hybrids (and many other Hippeastrum hybrids and species) are candidates for gardens in the lower South, where they’ll winter over with minimal protection.

Whatever their season or place of bloom, few bulbs bring greater cheer than the members of the Hippeastrum tribe.

Bulb Specialist Russell Stafford on the Best Spring Bulbs

Iris reticulata 'Michael's Angel' — The clear blue color of *Iris reticulata* ‘Michael’s Angel’ pairs beautifully with golden crocus.

Flower bulbs can’t be beat for bringing bursts of color to the garden. And they do it in such delightful fashion – their shoots thrusting up almost magically from the seemingly unoccupied ground in sudden crescendos of bloom. Then, just as suddenly, they pass from the scene, returning to the ground to wait out the months until their next brief fling.

The Siberian trout lily 'Altai Snow' is rare but worth seeking out. — The Siberian trout lily ‘Altai Snow’ is rare but worth seeking out.

Most garden bulbs (which botanically speaking comprise plants that grow from tubers, rhizomes, corms, true bulbs, or other underground storage organs) owe their fast and furious above-ground lifestyle to the short growing seasons that prevail in their native haunts. Many hardy “bulb” species, for example, hail from regions that receive most of their annual precipitation from late fall to early spring. The steppes and uplands of Central Asia – the ancestral home of many garden bulbs – are a place of long dry summers, cold bitter winters, and brief springs. Long, arid summers also characterize the climates of the bulb-rich Mediterranean and South African Cape regions.

Other bulb species are native to localized plant habitats that experience seasonal shortages of moisture or sunshine. Deciduous woodlands are the spawning ground of many of the most familiar shade-loving bulbs, which complete their above-ground growth in early spring before the canopy chokes out rain and sunlight.

Whatever their land of origin, most hardy bulbs need relatively moist, cool to cold winters and relatively dry summers, developing their roots in late autumn and winter and putting in an above-ground appearance for only a few weeks in spring or fall. Frost-tender bulbs, on the other hand, often come from regions in which rainfall and growth are concentrated in summer.

Corydalis, such as this Corydalis malkensis, come in many forms, all beautiful for spring. — Corydalis, such as this *Corydalis malkensis*, come in many forms, all beautiful for spring.

This is something to keep in mind when placing bulbs in the garden. Of course, a massed annual bedding display of hybrid tulips or hyacinths can be great fun and will work in just about any reasonably good soil. But a perennialized planting of less highly bred bulbs, artfully deployed in the appropriate garden habitat, can be equally compelling. Any garden niche that roughly mimics the conditions of a Central Asia steppe or a
Mediterranean chaparral or a temperate forest understory is fair game for a scattering of naturalized bulbs, which mingle beautifully with herbaceous and woody perennials that derive from the same natural habitat.

Reticulated irises (Iris reticulata and its hybrids) and “species tulips” (such as Tulipa humilis) make natural companions for penstemons, dwarf campanulas, plumbago (Ceratostigma plumbaginoides), low sedums, and other perennials that occur naturally in rocky steppe habitats. Likewise, crocuses, colchicums, cyclamens, and tuberous anemones look right at home with lavender, perennial candytuft (Iberis sempervirens), shrubby sages, and other small shrubs from the Mediterranean. And just about any partly shaded garden niche could benefit from a colony of woodland bulbs such as corydalis (including Corydalis solida) and trout lilies (Erythronium spp.).

A sunny garden site that dries out somewhat in summer is likely to be favorable for most sun-loving bulbs. In areas that are subject to summer rain and humidity, a well-drained soil works best. Rock gardens and troughs; embankments; wall plantings; sandy berms – all are ideal locations for grape hyacinths (Muscari spp.), ornamental onions (Allium spp.), and other steppe and Mediterranean natives. Quite a few sun-lovers (including many fritillaries and irises) absolutely require a dry summer rest, rotting away in warm moist conditions. Conversely, most woodland bulbs are relatively unfussy, thriving in just about any partly shaded site.

Species tulips (Tulipa bifloriformis shown) are often reliable perennials that spread over time. — Species tulips (*Tulipa bifloriformis* shown) are often reliable perennials that spread over time.

Whatever their favored exposure, bulbs tend to do best in relatively rich soil, and will usually benefit from a sprinkling of high-potassium fertilizer in early fall or spring. For excessively dry or heavy soil, incorporate a good amendment for fertility such as Fafard® Sphagnum Peat Moss and/or Compost. A general rule of thumb is to plant bulbs at a depth of 2 to 3 times their diameter (from the soil surface to their tips). Bulbs (such as crocuses and tulips) that are favorite morsels for chipmunks and squirrels may need protection such as a hardware cloth barrier (or interplant them with bulbs that rodents tend to avoid, such as narcissus and alliums).

The right bulbs in the right place will add a seasonal spark to any garden. Plant some this fall to reap your reward next spring, and beyond!

Flowering Shrubs for Fall

Lespedeza thunbergii 'Gibraltar' — The pink flowers of *Lespedeza thunbergii* ‘Gibraltar’ add welcome color to the late-season landscape.

Late summer and fall is a time when most gardens (and gardeners) could use a bit of a pick-me-up. And no plants are better suited for the job than the relatively few shrubs that flower in the growing season’s waning weeks. Whether used as single specimens to spice up drab niches, or combined with other colorful fall plants (such as autumn crocus, Japanese anemones, beautyberries, goldenrods, and sourwood) in a collective blaze of autumnal glory, fall-blooming shrubs are essential elements of a four-season garden.

Hibiscus syriacus 'Helene' — Hibiscus syriacus ‘Helene’ is one of the prettier varieties of this late-season bloomer.

Quite a few fall-blooming shrubs commence flowering in spring or summer, thus providing multi-season display. Among the longest-blooming of this lot is Daphne × transatlantica. A parent (along with Daphne cneorum) of the much more widely grown Daphne × burkwoodii, this small shrub produces flushes of bloom from mid-spring to fall, long after ‘Carol Mackie’ and other burkwoodii cultivars have ceased flowering. With its clustered, frosty-white, fragrant blooms and dainty, blue-tinged, semi-evergreen leaves, it makes an ideal candidate for a pathside or patio planting. Its variegated cultivar ‘Summer Ice’ has creamy-white leaf margins. Plants are hardy to USDA Hardiness Zone 5, and are best sited where their rather brittle branches will not be subjected to extra-heavy snow loads.

More familiar to gardeners are several other shrubs that flower from summer into early fall. Butterfly bush (Buddleia davidii) produces large candles of fragrant flowers in a range from violet to lilac-pink to white. Butterflies adore them. A somewhat cold-tender shrub, butterfly bush is root-hardy to USDA Zone 5, often dying to the ground in the colder sectors of its hardiness range. Even where it’s reliably root-hardy, it usually benefits from a severe pruning in early spring, growing to several feet tall by midsummer. Many cultivars are available, including the outstanding, compact hybrids ‘Ellen’s Blue’, ‘Blue Chip’, and ‘Ice Chip’. This species seeds itself profusely in warmer areas of its range, where it is sometimes considered a nuisance.

Chaste tree (Vitex agnus-castus), like Buddleia davidii, is a large, fragrant-flowered, butterfly-thronged shrub that usually dies to the ground in the northern fringe of its USDA zone 6 to 9 hardiness range (but attains tree-like proportions in warmer districts). The divided, five-fingered leaves are spicily pungent. Steeples of lilac-blue or white blooms appear from late summer to early fall, on stems that grow to several feet in a single season. Notable cultivars of chaste tree include blue-flowered ‘Shoal Creek’ and white ‘Silver Spire’. Vitex fanciers in USDA zone 5 might want to try chaste tree’s hardier relative, Vitex negundo var. incisa, which has more elegant, finely divided foliage and wispy sprays of lilac-blue flowers.

Rose of Sharon (Hibiscus syricacus) is yet another favorite that flowers from summer into early fall. The large, somewhat floppy blooms bear little resemblance to those of their namesake, nor do their lobed, vaguely maple-like leaves. First introduced to gardens in the sixteenth century (or earlier), this large shrub or small tree has given rise to numerous selections with floral colors ranging from blue to violet to burgundy to pink to white. Among the best are the sterile, white-flowered ‘Helene’ and ‘Diana’, which unlike most other cultivars will not self-sow. Hardy to USDA Zone 5, rose of Sharon will recover quickly and bloom if killed back in a severe winter (or if heavily pruned in early spring).

Buddleja davidii 'Peakeep' (PEACOCK™, ENGLISH BUTTERFLY™ SERIES) — The bright flowers of *Buddleja davidii* ‘Peakeep’ (PEACOCK™) will bloom until first frost. (photo by Jessie Keith)

The large, white, cylindrical flower clusters of panicle hydrangea (Hydrangea paniculata) typically appear in midsummer. The cultivar ‘Tardiva’, however, comes into bloom weeks later than most other selections, peaking in late summer and early fall. Lacier and more elongated than those of the familiar peegee hydrangea (Hydrangea paniculata ‘Grandiflora’), the flower clusters are especially large and late on plants that receive a severe pruning in early spring (plants grow to 7 feet tall in one season). This rock-hardy large shrub succeeds into USDA Zone 3.

In contrast to the above shrubs, Thunberg’s bush clover (Lespedeza thunbergii) concentrates all its bloom in September and early October, enveloping its arching branches in a lavish, vibrant display of rose-purple flowers. As with many late-blooming ornamental shrubs, it sometimes dies back in severe winters, returning from the ground to bloom the following autumn. It’s usually sold in the form of ‘Gibralter’, whose 6-foot stems splay under the weight of its prolific flowers. Other cultivars with pink or white flowers are sometimes available. For tidier winter looks, these shrubs can be pruned back in fall and mulched with Fafard Natural & Organic Compost to keep them protected through winter.

Last in flowering time but certainly not in garden value is a species from forests of central and eastern North America. In the wild, witch-hazel (Hamamelis virginiana) forms a large, often straggly understory shrub whose sparse, spidery yellow flowers are hidden among its yellowing leaves from early to mid-autumn. In the garden, however, it’s an entirely different animal – especially in the form of the recently introduced ‘Harvest Moon’. Bearing a showy profusion of relatively large flowers on naked branches, this cultivar’s floral display rivals that of winter-blooming witch-hazels such as ‘Arnold Promise’. Give it a good, humus-rich soil in sun to partial shade and it will develop into a dense 12-foot shrub that acquits itself well even when not dazzling onlookers with its fragrant, sunny blooms. Where space is limited, try ‘Little Suzie’, a compact, 5-foot witch-hazel selection that works well in foundation plantings, hedges, and other tighter niches.

Pruning Summer Flowers

Phlox paniculata 'Nicky' — Tall phlox are midsummer bloomers that will rebloom if the old flowers are pruned back. (photo by Jessie Keith)

Timely summer pruning is the key to more flowers – and less flopping – in the perennial (and annual and shrub) border. Many annuals and perennials bloom better and longer if their spent flowers are regularly pruned – a practice known as deadheading. In addition to boosting floral display, deadheading also prevents self-sowing by fecund perennials and annuals such as spiderwort (Tradescantia), garden phlox (Phlox suffruticosa), and mulleins (Verbascum).

Echinacea 'Marmalade' — Echinaceas produce seeds that are perfect bird forage, so you may rethink pruning their seedheads back.

Different plants favor different deadheading regimes. Some perennials require minimal deadheading other than a hard pruning back to their basal foliage as their last flowers fade. Among these are columbine (Aquilegia), Delphinium, most catmints (Nepeta) and Salvia, most perennial geraniums, lungwort (Pulmonaria), mountain bluet (Centaurea montana), and lamb’s ear (Stachys byzantina). Many of these will send up a second round of flowers later in the season.

Numerous long-blooming perennials – including bellflowers (Campanula), balloon flower (Platycodon), Jupiter’s beard (Centranthus ruber), Shasta daisy (Chrysanthemum × superbum), bee balm (Monarda), most Veronica, garden phlox, and daylilies (Hemerocallis) – do best with frequent deadheading of individual flowers or flower clusters. In most cases, the cut should be made just above the next bud or leaf below the spent flower(s).
Similarly, most long-blooming annuals benefit from regular, light deadheading, although heavier pruning may be necessary if growth flags in summer (as sometimes happens with diascias, sweet alyssum, and others).
Shrubby perennials that flower relatively briefly (e.g., goatsbeard and Cimicfuga) usually require nothing more than a single tip-pruning after they bloom.

Some plants are better not deadheaded, particularly if their seeds are valued for ornament (as with nigellas and shrubby Clematis), bird forage (e.g., echinaceas and rudbeckias), or self-sowing. Knowing when not to prune is also important!

Lamb's ears — Lamb’s ears always look better when the old bloom stalks are removed.

Deadheading is not the only type of pruning that benefits perennials. A good early-summer (or late-spring) shearing can do wonders for large, late-blooming species with unruly habits such as asters, Joe Pye weed (Eupatorium), and perennial sunflowers (Helianthus). Left unchecked, the statuesque stems of these perennials topple under the weight of their flowers.

A far better solution than trussing them with stakes and string after they flop is to cut them back halfway in June. Shorter, sturdier, swoon-resistant plants will result. Flowers may be a bit later and smaller than those of unpruned plants, but they’ll also be abundant and upright.
June is also the ideal time to prune lanky early-blooming perennials such as moss phlox (Phlox subulata), Dianthus, and perennial candytuft (Iberis). Sheared back halfway immediately after flowering, they’ll produce fresh basal growth and possibly a few repeat blooms. Straggly stems of lavender, sage, and other woody-based perennials respond well to pruning in early spring, before bloom.

Blanketflower will bloom until frost if you keep the seedheads clipped off.

And then there are shrubs. Weigela, mock-oranges (Philadelphus), Deutzia, and other shrubs of similar growth habit should be cut back hard to vigorous new lateral shoots that break growth as the flowers fade in late spring and early summer. These new shoots will eventually provide next year’s floral display. Unpruned shrubs from this group decline into a lanky mass of leggy stems topped with old, unproductive wood that chokes out new growth.

Numerous other spring-blooming shrubs (including rhododendrons and lilacs) exhibit a somewhat different growth pattern, bearing relatively short new shoots mostly at their tips. Consequently, they generally do best with a relatively light early summer pruning, with care taken to preserve as much new growth as possible (which will give rise to next year’s flowers).
Whatever the plant – shrub, perennial, or annual – it will respond well to a post-pruning application of a nutrient-rich compost such as Fafard Natural & Organic Compost. Fertile soil and proper pruning make for happy plants (and gardeners!).

Battling Garden Weeds Naturally

A hand hoe with flowers — A good hand hoe makes the weeding process much easier!

Weeds are half the battle of gardening. And the key to winning that battle is to know your enemy.

Cover the Soil Seed Bank

Weeds use several strategies to sneak into your garden. One is via the soil seed bank. Each cubic foot of soil typically contains hundreds or even thousands of weed seeds (some of which remain viable for decades). Turn the soil, and you will likely liberate enough buried seeds to turn your garden into a weed party. To prevent this from happening, keep those seeds well buried. Shallow-till only, and if any weeds do germinate, use the appropriate strategy to control them (see below). If you must deeply disturb the soil, follow up with some mulch to inhibit weed germination, or with a couple of shallow hoeings to inhibit seed germination and establishment. A scuffle hoe or Japanese hand hoe should be in the weaponry of any serious gardener.

Celandine (Chelidonium majus) — Celandine (*Chelidonium majus*) is a problematic weed in New England.

Weed Seed Solarization

Summer solarization is another strategy for dealing with soil disturbance. Rake and level the disturbed area, water it thoroughly, and cover it (and a 1-foot margin) with clear greenhouse polyethylene. Remove the poly in a month or so, after the weed seeds have been thoroughly cooked.
Herbicides should be a last resort and are usually not necessary.
Weed seeds can also arrive from outside the garden, mostly by air (think dandelions) or via introduced soil and soil amendments (compost, potting mix, etc.). Thwart airborne seeds by removing or cutting back neighboring plants that might have your garden on their flight itinerary. Mulched, densely planted gardens are less vulnerable to seeds that do manage to fly in.
Seeds that arrive by soil require a different kind of vigilance (and wariness). Any soil or soil amendments from outside the garden should be considered guilty of weed seed contamination until proven innocent. Always err on the side of caution when adding them. Fafard products such as Fafard Garden Manure Blend and Natural & Organic Compost make safe and reliable conditioners for your soil.

Pokeweed is a common weedy pest across much of the eastern United States.

Some weeds invade not by seed but by rampant vegetative growth such as underground rhizomes. Plants with thuggish growth habits are best kept at a distance from those of more restrained growth. When this is not possible (as when lawn abuts a perennial bed), a good half-moon edger is an indispensable tool for keeping pushy neighbors at bay. Cut a 2- to 4-inch-deep mini-trench, sloped toward the garden side and steep-walled toward the lawn side. Physical barriers such as plastic or metal edging (or a good wide path) can also work to separate plants that have incompatible behaviors.

Whatever measures you take to exclude them, some weeds will invade – and the best way to deal with them depends on which lifestyle they follow. Shallow tilling makes short work of most annual and biennial weeds, as do flame weeders and dehydrating fatty-acid herbicides (such as Avenger). Pulling these short-lived plants is wasted effort or worse because it often brings weed seeds to the surface along with the roots.

Shallow tilling will also eliminate most clump-forming, fibrous-rooted perennials, although some will require repeat treatments. Aggressive or tap-rooted perennials pose greater challenges, however. Once established, they can be virtually impossible to eradicate. Quackgrass (Elymus repens), bindweed (Convolvulus arvensis), pokeweed (Phytolacca americana), red sorrel (Rumex acetosella), celandine (Chelidonium majus) and curly dock (Rumex crispus) are among the weeds that will wreak horticultural havoc if they’re allowed to set up shop in your garden.

It all comes back to knowing your enemy. If you know your local weeds and their growth patterns, you’ll also know the best way to respond.

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