Archive: May 2016

  1. 2016 GCA Summer Tour in Portland, Oregon

    Come out and see us at the GCA Summer Tour in Portland, Oregon from June 26th to June 29th! It’s the best way to get an exclusive, behind-the-scenes look at the garden centers of the region. The Portland are2016_GCA_Tour_logoa boasts loads of fantastic IGCs offering rare and unusual plants and lots of fantastic merchandise for the industry. You won’t want to miss it!

  2. Hardy Geraniums, the Perfect Perennials

    Geranium 'Anne Thomson'

    Geranium ‘Anne Thomson’ (photo by Jessie Keith)

    Hardy geraniums will not cure baldness, ensure world peace or transform chocolate cake into a healthy food, but they are the answer to a wide range of garden questions. Do you need a perennial ground cover to disguise the wretched remnants of spring daffodil foliage? Try bigroot geranium (Geranium macrorrhizum), with pink flowers and apple-scented leaves that redden in the fall. Is your garden in need of a flowering plant that will flourish in shade? Waste no time in snapping up the shade-tolerant Geranium phaeum. Does your heart ache for a well-mannered, weed-stomping carpet to plant at the feet of that brand new hydrangea? Try Geranium x cantabrigiense ‘Biokovo’, an award-winning white-flowered hybrid with gorgeous lobed leaves.

    Geranium 'Rozanne' PP12175

    Geranium ‘Rozanne’ (photo by Jessie Keith)

    Hardy geraniums, sometimes called “cranesbills”, belong to the same family as the showy window-box geraniums that adorn outdoor spaces from Memorial Day through the end of summer. Everyone, from your grandmother to your nosy neighbor, refers to those big-headed specimens as “geraniums”, but they are known botanically as Pelargonium. Lovely as they are, pelargoniums are not winter hardy in much of the United States. Hardy geraniums, on the other hand, are often reliably perennial in cold-winter climates. In place of the large, domed flowerheads characteristic of pelargoniums, hardy geraniums most often bear single, five-petaled blooms in shades ranging from purest white to near black. Many of the most popular varieties feature pink or purple flowers, sometimes with contrasting veins.

    Good garden centers and specialty nurseries offer an array of hardy geraniums, making choice the biggest challenge. To figure out the answer to your particular geranium question, take stock of the available growing space and light availability, and consider some of the following beautiful and useful cranesbills just waiting to find homes in your garden.

    Sun Lovers

    Geranium phaeum 'Lily Lovell'2

    Geranium phaeum ‘Lily Lovell’ (photo by Jessie Keith)

    Horticultural experts in high places, like England’s Royal Horticultural Society and America’s Perennial Plant Association, have decreed that ‘Rozanne’ is nothing short of a miracle plant. The one-inch flowers are among the bluest found in the geranium clan, with five blue-purple petals surrounding a pale blue-white central “eye zone”. Reblooming at regular intervals throughout the growing season, ‘Rozanne’ also provides deeply dissected foliage that turns red in the fall.

    “Bloody cranesbill” is an evil-sounding common name for Geranium sanguineum, a lovely law-abiding plant with pink flowers accented by darker red veins. Variety lancastriense features darker pink blooms than the species. Growing only ten inches high, the plants spread into pretty mounds, with dissected, medium green foliage. The spring-blooming ‘Album’ cultivar has all the virtues of other sanguineums, plus pristine white petals. It tends to self-sow, but is never uncivilized in the process. Besides, the flowers are so beautiful that self-sowing is a virtue.

    Geranium x cantabrigiense 'Biokovo'

    Geranium x cantabrigiense ‘Biokovo’ (photo by Jessie Keith)

    Biokovo cranesbill (Geranium x cantabrigiense ‘Biokovo’), a spontaneous hybrid named after the Croatian mountain range where it was discovered, bears lovely rounded leaves that are at least semi evergreen in many climates. Spreading nicely over time, this geranium, another Perennial Plant Association “Plant of the Year” winner, bears delicate white spring flowers with prominent red stamens.

    The garden world would be poorer by far without bigroot geranium and its various offspring. Its fragrant, palmate leaves are a great foil for the numerous pink spring flowers. The blooms of ‘Bevan’s Variety’ are a little darker than the species. All bigroots spread if they are happy and their undemanding nature makes achieving that happiness easy. If bigroot geraniums happen to stray into light shade, they will still perform well.

    Shade Lovers

    Geranium 'Album'

    White-flowered hardy geranium

    The hardy geranium tribe is also home to numerous species and varieties that thrive in light to partial shade, with some that will even prosper under trees. One of the best known is Geranium phaeum. Like bloody cranesbill, it suffers from grim nicknames, including “dusky cranesbill” and “mourning widow”. Native to parts of Eurasia, including Croatia, the “widows” are distinguished by reflexed petals that range in color from the white of ’Album’ through shades of mauve to the deepest purple-black of ‘Raven’. All are attractive without being flashy. Some Geranium phaeum varieties provide extra value by bearing variegated foliage. The distinctive pointed leaves of the purple-flowered ‘Samobor’, for example, are mottled with large, maroon purple blotches.

    Geranium nodosum is another good choice for shady spots. The species features maple-like lobed leaves and purple flowers, accented with darker veins. Making a slightly louder statement, the fashionably-named ‘Svelte Lilac’ variety boasts flowers with lighter “eye zones” and brighter green leaves.

    Cranesbills are almost always billed as being deer and other varmint resistant, not to mention tolerant of various soils and climate conditions. Start them right by amending the soil before planting with a high quality mixture like Fafard® Premium Natural & Organic Compost or Premium Topsoil. Water regularly until the young geraniums are established. Once flowering is through, shear back the foliage to keep plants looking attractive and stimulate new flowers in reblooming varieties, like ‘Rozanne’.

    In addition to their other virtues, most happy cranesbills will eventually form large clumps that are easy to divide and use elsewhere in the garden or donate to lucky gardening friends. For beauty, ease of care, and the ability to cloth garden beds, containers, and even rock wall niches with loveliness, hardy geraniums are a great investment.

  3. Gardens with a Silver Lining: Silver-Leaved Plants

    Eryngium

    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.

    OLYMPUS DIGITAL CAMERA

    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)

    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.

  4. Waterwise Container Gardening

    Pentas JaKMPM

    Pretty pink pentas and purple-leaved pennisetum are both drought resistant and look great in containers.

    Container plantings are notorious for drying out quickly and needing extra water through the worst summer months, lest they dry and shrivel in a day’s time. Miss one morning watering and the most beautiful contained petunias or impatiens can go from great to a ghastly full wilt by evening. Thankfully, there are ways to reduce the need for daily container watering while also ensuring lots of pretty potted plants for porch and patio.

    The four factors to consider when designing water-wise container gardening are 1. pot size and type, 2. soil and soil additives, 3. plant drought tolerance, and 4. pot placement. Get these factors right and your containers may require half the water normally supplied to summer pots.

    Container Size and Type

    Glazed and plastic pots hold water better than terracotta. (image care of the National Garden Bureau)

    Glazed and plastic pots hold water better than terracotta. (image care of the National Garden Bureau)

    Container size and type are things that most gardeners don’t consider as water-saving, but the larger and more water impermeable the pot, the more it will conserve water. Think about how plants move water. They take it up through the roots, the water travels through the plant, and then it’s released from tiny pores in the plant’s leaves and stems. Basically, the plant pulls water from the soil. A larger pot holds more water and provides more root space—offering a bigger well of needed moisture. And, an impermeable pot surface simply means that less water will be lost due to evaporation. Terra cotta pots are the worst when it comes to evaporation while glazed ceramics and plastic or resin pots keep water at the root zone.

     Soil and Additives

    1722fafard Ultra Container with Extended Feed RESILIENCE front WEBSome soils and amendments like peat moss hold water well and others like perlite encourage drainage. Our best water-holding potting soils contain lots of rich organic matter in addition to water-reserving additives, such as the Moisture Pro™ water-holding crystals Fafard® Ultra Container Mix with extended feed and RESiLIENCE®. The RESiLIENCE® additive, which is OMRI-listed for organic gardening, helps plants further by helping plants reduce water stress during hot, dry times. The addition of coco coir (we recommend Black Gold Just Coir) or Fafard Canadian Sphagnum Peat Moss further enhanced water-holding to reduce the need to water every day.

    Drought-Tolerant Plants

    Lantana camara 'Bante Rossa' (BANDANA™ ROSE, BANDANA™ SERIES) PP18148 JaKMPM

    Lantana camara BANDANA™ ROSE

    There are so many beautiful container-friendly garden flowers that stand up to heat. For containers, it’s great to choose heavy-flowering annuals that look nice until frost—either with their foliage, flowers, or both. It’s also nice to try new garden center offerings, in addition to solid standbys, that will wow and impress.

    Pennisetum glaucum 'Jade Princess' JaKMPM

    Pennisetum glaucum ‘Jade Princess’

    For warm container color, try the new Bidens Campfire® Fireburst with its tiny hot daisies of orange-red and gold. Annual Bidens bloom continuously and look great alongside the red and orange flower of Lantana Rose Bandana, and gold-, -orange, and magenta-flowered Zinnia Pinwheel Mix, which are also compact. All stand up to hot, dry weather once established. The outstanding Cuphea Vermillionaire® is another super tough, super pretty bloomer producing lots of orange-red, tubular flowers through summer that attract hummingbirds. These glow container plantings when placed alongside tall, Angelonia Angelface® Superwhite and soft, airy Mexican hairgrass (Nasella tenuissima). Another great hummingbird flower for heat and containers is the new Salvia Ablazin’™ Tabasco with its taller stature and scarlet flowers that shine alongside the chartreuse leaves and purple plumes of Pennesetum glaucum ‘Jade Princess’.

    Containers of bold succulents are also welcome for those wishing to water as little as possible. Pots of colorful Agave, Aloe, cacti or sedums look great through summer and can be brought into a sunny indoor spot through winter. The only caveat is that these plants tend to want a better-drained soil, such as Black Gold Cactus Mix.

    Container Placement

    IMG_9028Where you place your plants can make a big difference in how quickly they lose water. Exposed areas with hot sun and wind will always dry plants out more than protected areas shielded from the wind and sheltered from the sun during the hottest time of day. Morning and afternoon sun is always less beating, so place planters in spots where this level of sun dominates and light shade it provided around noon.

    Planning ahead with these four steps for water-wise containers will save water, time, and headaches through summer. Your containers will still need regular care and water for best health and looks, but you will be able to enjoy them more and worry less about summer container insta-wilt.