Articles

Late-Summer Flower Garden Renewal

Hibiscus 'Disco Belle Pink'
Hibiscus ‘Disco Belle Pink’ is a reliable late-summer bloomer.

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.

Cheap Annuals

Petunia 'Madness Red' (MADNESS™ SERIES)
End-of-season petunias are cheap and will brighten up the late-season garden if given a little TLC. (Photo by Jessie Keith)

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

Coreopsis verticillata 'Golden Gain'
Tickseeds, such as the compact Coreopsis verticillata ‘Golden Gain’, will bloom towards season’s end with a little deadheading and care. (Photo by Jessie Keith)

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.

Magnificent Mallows

Echinacea purpurea 'Pink Double Delight'
There are so many unique and pretty coneflowers for the garden, such as this Echinacea purpurea ‘Pink Double Delight’. (Photo by Jessie Keith)

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.

Read more summer gardening articles:
Protect Plants from Summer Heat
Pruning Summer Flowers

Architectural Perennials for Beautiful Landscapes and Gardens

Wild senna marilandica
Wild senna (background with yellow flower) is a big, bold perennial that’s great for large sunny flower borders.

It takes all types to make a perennial border, from seasonal thrillers (such as oriental poppies and hybrid tulips) to carpeting fillers.  But no type is more valuable than the sort that is tall and trouble-free and has handsome foliage that doesn’t quit.   Such dominant, “architectural” perennials are perfect for providing the structural backbone of the border, punctuating and unifying it with season-long form and texture.

Amsonia montanaMany of the best architectural species for sunny borders hail from the prairies and meadows of central and eastern North American, where big, beautiful perennials reign supreme.

Eastern bluestar (Amsonia tabernaemontana), for example, occurs in moist open habitats from the upper Mid-Atlantic to Texas.  A variable plant in the wild, in cultivation it typically forms 3- to 4-foot-tall clumps of sturdy upright stems clothed with slender, willowy, lance-shaped leaves.  The foliage stays healthy and lush all growing season.   Clusters of powder-blue, star-shaped flowers cover the plant in mid-spring, and the leaves glow butter yellow in fall.  This long-lived species will thrive for decades in fertile, humus-rich garden soil. (Sandy or clay soil can be amended with a good amendment, such as Fafard Premium Topsoil).

Actaea rubifolia
The leaves of Actaea rubifolia are very large and textural.

Several other bluestar species are also well worth growing, especially Hubricht’s bluestar (Amsonia hubrichtii), whose narrow, ribbon-like leaves form feathery 3-foot mounds.  It, too, blooms blue in spring and turns buttery yellow in fall. The compact hybrid cultivar ‘Blue Ice’ is likely the best of all Amsonia for the garden, though its tidy, compact stature is less bold and architectural than most species.

Wild indigo (Baptisia australis) shares Eastern bluestar’s general geographic range, bloom time, stature, and longevity.  Its spires of violet-blue flowers, however, are a different thing entirely.  So, too, are its grayish-green, three-parted leaves and large, inflated seed pods.  Plants emerge relatively late in spring, the asparagus-like new shoots developing rapidly into leafy 3- to 4-foot domes (or 18 to 24 inches in the case of subspecies minor).  Yellow wild indigo (Baptisia sphaerocarpa) does much the same thing, but with grayer foliage and luminous yellow flowers.  It’s also more adaptable to dry sites, making it a good choice for xeric gardens.  White-flowered wild indigo species include lofty white wild indigo (Baptisia alba) and the relatively compact longbract wild indigo (Baptisia bracteata var. leucophaea), which holds its creamy blooms on gracefully bowing stems.

Aralia racemosa
Aralia racemosa is striking in the landscape.

Yet another lordly legume from the central and eastern U.S., wild senna (Senna hebecarpa) produces bright yellow midsummer flowers on towering stems that can reach 6 or 7 feet in sites with moist, fertile soil.  The pinnate, ferny leaves give it a light, airy presence, despite its imposing size.

The same can be said of Culver’s root (Veronicastrum virginicum).  Its majestic, 4- to 6-foot stems carry well-spaced, star-like whorls of narrow, pointed leaves, to elegant, almost weightless effect.  Candelabras of frothy white or pink flowers develop atop the stems in midsummer.  Like wild senna, it grows best in full sun to light shade and moist, relatively fertile soil, and is native to much of central and eastern North America.
Fafard Premium Topsoil pack

The steppes of Central Asia are another hotbed of large, handsome perennials, including the misleadingly dubbed Russian sage.  In fact, Perovskia ariplicifolia (and its near-twin, Perovskia abrotanoides) is from Afghanistan, Pakistan, and Tibet, rather than Russia.  No matter; it’s still among the best architectural perennials for hot, sunny garden habitats with dry, lean soil.  Technically a subshrub, it sends up 2- to 5-foot, silvery stems from a low, woody framework.  Dainty, fuzzy, aromatic leaves line the stems’ lower reaches, below branching clusters of misty lavender-blue summer flowers.  Numerous selections and hybrids of the species are available, including lace-leaved ‘Filigran’ and dwarf ‘Little Spire’.

Aralia racemosa inflorescence
The starry flowers of Aralia racemosa add unique appeal to shaded gardens.

Two of the finest groups of perennials for shady gardens have both Asian and North American roots.  The genus Aralia offers architecture aplenty, comprising some of the supreme foliage plants for partial to full shade.  Eastern North American native spikenard (Aralia racemosa) gradually matures into a 4- to 6-foot clump of immense compound leaves that suggest something tropical.   Sprays of small, white, starburst flower clusters stand tall in midsummer, ripening to purple berries.   Some forms of spikenard have burgundy-purple stems that add to the drama.  East Asian aralias include A. cordata and its radiant chartreuse-yellow cultivar ‘Sun King’.

Members of the erstwhile genus Cimicifuga (recently lumped into Actaea) also loom large in the shady perennial border, both literally and figuratively.  With their artfully divided leaves and showy candles of fragrant white flowers, bugbanes are perfect for bringing life and light to the garden.  Maroon-leaved cultivars such as ‘Black Negligee’ are the current darlings of designers, but perhaps the gem of the genus is Actaea rubifolia, from the mountains of the Southeast U.S.  The luxuriant, jagged, maple-like foliage alone puts it in the first rank of perennials, and its showy white wands are the equal of any bugbane.