In August, high summer is well established. Drought and hot weather have generally taken their toll on gardens and gardeners, both of which may look and feel a little tired. Caught between the tail end of the daylilies and the beginning of the asters, the holes in the borders begin to fill with crabgrass and other evil weedy entities. We all want our plantings to look lovely, but when it is 95 degrees F in the shade the usual urge to dig in the dirt or refresh the containers is tempered by a natural reluctance to lift more than two fingers.
What to do? A bit of inspiration won’t cool things off, but it may make the garden look better. The following are a few easy-to-grow and easy-to-love plants that are in bloom now and can improve the look of late summer beds and pots.
Most garden centers still have a few summer annuals left, generally lurking on the sale tables or grouped into mixed container arrays. The garden centers want them out, and as long as the plants are still relatively pretty and healthy, you can use them to refresh your garden plantings. A few of these plants will be goners, but many simply need liberation from the pots that have housed them since spring, a bit of pruning or pinching back, a judicious amount of liquid plant food, and a fair amount of water. Leggy petunias, sad impatiens, and seemingly spent snapdragons usually take to tender loving care and will respond by bouncing back and blooming nicely until frost.
Go to the garden center early in the morning, late in the afternoon, or on a cloudy day. Bring your bargain plants home, apply the restorative treatments right away, and pop them in place in the cool of the evening. Don’t be afraid to disaggregate mixed containers and install the individual plants wherever you need them. Mixed containers are all marriages of merchandising convenience anyway.
Now and Later Perennials
When you take your cool-of-the-day trip to the garden center, keep an eye out for perennial species and varieties that are in bloom now. Black-eyed Susans (Rudbeckia spp.) and their relatives, the ever-increasing coneflower clan (Echinacea spp.), are in bloom at nurseries all over the country and will multi-task when you get them home, supplying color now and the promise of the same thing next year at this time. Their daisy-family kin, the tickseeds (Coreopsis spp.) are also in bloom and should produce at least one more flush before frost if you deadhead them at planting time. Look for reliable, tried-and-true varieties found at almost any nursery, such as the classic Coreopsis ‘Moonbeam’ with its vigorous habit and numerous pale-yellow flowers, and Echinacea purpurea ‘Magnus’ with its large pink flowers with dark cones.
Less formal perennials of late summer include Joe Pye-Weed (Eupatorium purpureum, 5-7′) a late summer star, especially for informal, cottage-type gardens or native borders. This lofty perennial may not fit all garden sizes, so those with smaller borders may consider planting the somewhat shorter Joe Pye-weed, Eupatorium dubium ‘Little Joe’, which reaches only 3-4′ in height. All Joe Pye-weeds are stellar butterfly plants. Wand flowers (Gaura spp.) are also great late-summer butterfly plants that are airy, beautiful and generally drought tolerant. The delicate variety ‘Pink Fountain’ is one of several pink-flowered forms that shine at this time of year. Use them in mid-border or medium-size pots for stature and delicacy.
Late summer is prime time for striking members of the mallow family, including shrubs like rose of Sharon (Hibiscus syriacus) and bodacious perennial bloomers like hardy, native, swamp mallow (Hibiscus moscheutos). Both are widely available at nurseries and garden centers and bear large, prominent hollyhock-like flowers combined with attractive foliage. Plugging a few mallows into a mostly fallow flower garden will add instant impact. A container full of ‘Disco Belle Pink’ swamp mallow, with its enormous pink flowers, or large, red-flowered ‘Heartthrob’, will light up even the most uninspired space.
The large, bushy swamp mallow requires full to partial sun and can be grown either in-ground or in large containers. If you try growing one in a container, start with a high-quality, moisture-retentive potting medium, like Fafard® Ultra Container Mix With Extended Feed. Late summer mallows, especially the swamp type, are moisture lovers and the moisture-holding crystals in the Fafard mix will keep the plants happy, even during the inevitable dry spells.
Planting at the day’s coolest or cloudiest times will help new plants and heat-depleted gardeners stave off stress. Be sure to water in plants as they are installed and the water daily, if necessary, until the weather starts to cool off. After that, relax. Your garden will have inspired the neighbors, even during summer’s dog days, and you will be ready to start thinking about all those bulbs that you ordered while sitting in front of the AC in August.
Hardy geraniums will not cure baldness, ensure world peace or transform a chocolate cake into 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.
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.
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.
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.
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 =or 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.
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.
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.
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).
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.
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.
Few gardeners feel ambivalent about common garden gladiolus (Gladiolus x hortulanus). In the decades since the first large-flowered hybrids were developed in the late 1830s, the tall flower spikes have been in and out of fashion many times. But glads and the gardeners who love them are nothing if not persistent. Even when horticultural fashion arbiters ignore the genus, the many-colored blooms show up in all kinds of places, from the end rows of vegetable gardens to carefully tended perennial borders and florists’ bouquets.
The tall garden hybrids are impressive, but the genus is full of other winning plants, including petite species and varieties that are well suited to container and small garden culture. Many species glads have an informal look that is more reminiscent of the wildflower garden than the florist shop. Some are also fragrant. All gladioli share the characteristic long, sword-shaped leaves and summer bloom time.
The following is a brief guide to some of the stars of the gladiolus galaxy.
These are the plants that come to mind when most people hear the word “gladiolus.” All grow from corms that are tender in cold winter climates. Standard grandifloras soar between 3 and 6 feet tall. The trumpet-shaped individual flowers, which can be up to 6 inches wide, open from the bottom of the spike to the top. Vendors carry scores of named varieties in just about every imaginable color. Bi-colored glads are available in an amazing array of combinations. Breeders have also developed shorter, dwarf varieties, including the vividly marked “butterfly” types, which reach only 1 to 3 feet.
These plants, formerly known as Gladiolus primulinus, are now classified as Gladiolus dalenii. Somewhat shorter, at 2 to 4 feet tall, the individual blossoms are hooded, rather than open like the grandiflora types. They also tend to be smaller and less crowded on the stems, giving the plants an informal feel. The primulinus glads are especially useful to cold winter gardeners, because they are hardier than grandifloras. Some varieties, like golden-apricot ‘Boone,’ are cold hardy to USDA zone 6.
Also smaller and less formal than the grandifloras, the Nanus Hybrids, bred from Gladiolus nanus, bear up to three slim flower stalks with up to ten relatively small individual flowers. These cold-tolerant miniatures may also feature distinctive markings.
Native to the Mediterranean, Gladiolus communis var. byzantinus blooms somewhat earlier than grandiflora types and is also more cold-tolerant. The 24- to 36-inch stems are slender and arch gracefully, bearing ten to twelve individual, open magenta flowers per stem. Byzantine glads bloom earlier than their large-flowered relatives and naturalizes readily. They are fixtures in old southern gardens and have often been passed along from gardener to gardener.
Formerly known as Acidanthera, Abyssinian gladiolus (Gladiolus callianthus ‘Murielae’) has a distinctive, orchid-like appearance and a pronounced fragrance. Introduced in the late nineteenth century, the blossoms feature sharply pointed white petals with dark purple centers. Abyssinian glads grow on slender stems that rise from 3 to 4 feet in height.
Gladiolus corms should be planted 4 to 6 inches deep in rich, well-drained soil. Before planting, amend heavy clay soil with organic material like Fafard Garden Manure Blend or Fafard Natural and Organic Compost Blend. For container-grown specimens use a complete potting medium such as Fafard Ultra Potting Mix With Extended Feed. Tender gladiolus hybrids can be grown as annuals in cold weather climates. To keep desirable varieties from year to year, lift the corms in fall and store in a dry, frost-free location. Replant in spring after all danger of frost has passed. Grandiflora types may need stakes or other support to prevent the heavy flower stalks from flopping, but shorter varieties can stand on their own.
Gladioli are sometimes known as “sword lilies” for the sword-like shape of their foliage. Arm your beds and borders with these “swords” and they will cut through the summer garden doldrums.
Consider the lilies, for example. The voluptuous, richly hued blossoms of these fleshy-bulbed perennials are just the thing for alleviating the dullness that sometimes descends on the post-spring garden.
Early summer welcomes the typically flat-faced, upright, freckled blooms of the Asiatic Hybrids, which flower in warm hues of yellow, orange, red, and pink, as well as white. Numerous narrow leaves clothe their sturdy, 1- to 4-foot stems. Hundreds of Asiatics have been introduced over the years, including the famed ‘Enchantment’, whose orange, dark-speckled blooms still frequently appear in bouquets.
Arriving somewhat later, the Oriental Hybrids carry the delicious fragrance and rosy-or-white, purple-flecked, often gold-emblazoned coloration of their two primary parents, Lilium speciosum and Lilium auratum. The large, waxy, bowl-shaped flowers with slightly backswept petals open on 2- to 4-foot stems, which are rather sparsely set with relatively broad, green to blue-green leaves. Nodding to outfacing flowers are the rule, but some cultivars have semi-erect blooms (including rose-red, white-edged ‘Stargazer’).
Blooming alongside the Oriental lilies (but usually above them, on 4- to 6-foot stems), Trumpet Hybrids are noted and named for their huge, spicy-scented, funnel-shaped blooms. Notable selections include the African Queen Strain, which flowers in various shades of cantaloupe-orange. Prone to toppling because of their colossal proportions, Trumpets often need staking (or a sheltered position) to keep them upright. In recent years, the Trumpets have been interbred with the Oriental Hybrids to create a popular new class of showy-flowered hybrids, the Orienpets, which add to their usefulness by having flop-resistant stems.
Among the many Lilium species well worth growing are Turk’s cap lily (Lilium martagon) – which has parented some beautiful hybrids of its own – and Eastern North American natives such as Canada lily (Lilium canadense) and wood lily (Lilium philadelphicum).
Whether species or hybrid, most lilies do best in full to partial sun and a fertile, humus-rich soil. Or grow them in deep containers fortified with Fafard Premium Natural & Organic Compost Blend. Unfortunately, all lilies have two potentially mortal enemies: viruses and the dreaded red lily beetle. Many hybrids and species shrug off viruses, but all are red-lily-beetle-susceptible, and any lily planting in a beetle-infested area will need protection, either by hand-picking or by spraying. Releases of parasitic wasps in Rhode Island have resulted in dramatic local reductions of red lily beetle numbers, so there’s hope that this bête rouge will soon make its exit.
Lovely and varied as they are, lilies are far from the only valuable hardy summer bulbs. Other worthies include the following bulbs for summer.
Crocosmia hybrids, with long, curving midsummer spikes of dazzling, often fiery-hued blooms that attract hummingbirds. Although hailing from southern Africa, these sun-loving perennials include a few hybrids hardy to USDA Zone 5 (such as the smoldering orange-red ‘Lucifer’). Plant their crocus-like corms in rich soil that doesn’t dry out in summer.
Several species of Lycoris, East Asian bulbs which bear clusters of fragrant amaryllis-like blooms on tall, naked stems that magically arise in mid- to late summer. Far too rarely seen in gardens or catalogs, hardy Lycoris are most often represented by the lilac-pink-flowered Lycoris squamigera. Other showy hardy species include gold-flowered Lycoris chinensis; creamy-yellow Lycoris caldwellii; white Lycoris longituba; and white, rose-striped Lycoris incarnata. All produce strap-shaped leaves in spring, which die back months before the flowers appear. Hardy Lycoris remain almost unknown in American gardens, despite numbering among the most beautiful summer-blooming perennials. Their narcissus-like, fleshy-rooted bulbs store poorly, contributing to their obscurity. Purchase freshly dug or container-grown bulbs, and plant them in good soil in full sun or light shade.
Numerous East-Asian species of Arisaema, the genus that also includes Jack-in-the-pulpit (Arisaema triphyllum). Their hooded inflorescences range from bizarre to beautiful, and their spoked or lobed, compound leaves are often equally remarkable, and sometimes gargantuan. Perhaps the queen of the tribe is Arisaema candidissimum, which in early summer sends up a large, ivory-white, green-streaked hood surmounted by an enormous, broadly three-lobed leaf. The flowers cast a faint, sweet scent. These Asian Jacks tend to want more sun than the native, and less winter moisture. Mark the places where you plant their tubers; they may not break ground until late June.
A host of ornamental onions. In most cases, summer-blooming alliums grow from slender, scallion-like bulbs and have persistent, grassy leaves (unlike the early-dormant spring-blooming species). Lovely but little-known summer alliums abound, including Allium ramosum, a white-flowered beauty which blooms earlier and self-sows much less rampantly than the otherwise similar garlic chives (Allium tuberosum); Allium togashii, an August-blooming pixie with bright lilac-pink heads; and the elfin, blue-flowered Allium sikkimense.
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