Just when the days begin to grow a bit shorter and many blooms have begun to sputter, a fresh explosion of flower power reassures Yakima gardeners that summer’s fireworks are not over yet. When it comes to dahlias, September is spectacular. Dahlias have waited until now to unfurl one of the most expansive palettes of flower colors, forms and sizes of any plant, and will continue to fill bouquet after bouquet until the first frost.
But life has not always been charmed for the dahlia, which has often been snubbed by more sophisticated gardeners. Perhaps it’s because influential English gardener Gertrude Jekyll commented that “the dahlia’s first duty in life is to flaunt and to swagger.” She may have had in mind “dinner plate” dahlias, which sport flowers that can be more than a foot in diameter. If their names are descriptive — “Kelvin Floodlight,” “Bodacious,” “Babylon Red” or “Gladiator” — she may have had a point. But if you want something less audacious (striking, but short of the tight red dress and stiletto heels), you can choose from cactus-flowered dahlias, water-lily dahlias, peony-flowered dahlias, orchid dahlias, anenome dahlias … the array is endless. And colors can be subtle or dramatic. While the mark of a refined, Jekyll-approved garden has been the use of many complementary foliages, textures and forms, vivid, vibrant and adventurous color is back — and when it comes to color, count on dahlias to deliver.
Still skeptical? Start with the “Bishop,” “Mystic” or “Happy” series, which feature small, simply formed dahlias in an array of saturated colors that harmonize with other perennials. If that isn’t enough, the filigreed foliage comes in exotic eggplant purple or bronze, the 3-foot stems do not require staking and the plants take well to containers. What could be more refined?
All dahlias grow from tubers, which look more like sweet potatoes with an “eye” at one end. These tubers are actually modified stems that store nutrients and water underground while sending up the tall, leafy stalks that eventually shoot forth flowers. Tubers are planted in the spring and then dug and stored in a frost-free area after the first frost in cold-winter areas such as ours. I consider this task to be one of the rites of autumn, like raking leaves and bringing in the hoses. I store freshly dug tubers in paper grocery bags in the basement and bring them out in the spring to divide and replant. At the end of the growing season, when you dig your dahlias out for winter storage, you will find not one tuber but four to a dozen tubers, each with an “eye” that holds the promise of a fresh flush of flowers next season. Dividing dahlia tubers is easy, so you’ll have more dahlias to plant, share or trade with other gardeners.
Busy gardeners can be put off by the necessity of lifting and storing the tender tubers for the winter and then hauling them out again for spring replanting. Some creative Yakima Master Gardeners have been successful in overwintering their dahlias in their garden beds. One technique is to cut back on water in late September, so that the growing season ends with fairly dry soil. As soon as November arrives, the stalks are cut down close to the ground and the bed is covered with heavy plastic that stays in place over the winter, keeping the bed dry despite rain and snow. This is a good thing because tubers can rot in cold, wet soil. When the earth warms again in spring, the plastic is removed, and the dahlias begin to send up new shoots.
Another technique is to plant the tubers 8 inches deep, slightly deeper than usually recommended, but at a level of the soil that is likely to remain unfrozen during most winters. After a hard frost has brought the plants down, the dead foliage is removed and the entire bed is covered with 6-8 inches of good compost or any other substantial mulch.
Does this still sound like too much work? Dahlias are fairly inexpensive, with most tubers costing less than $5. There is no guilt in treating your dahlias as annuals, enjoyed for a single season. If you leave the tubers in without protection and they freeze and perish, consider it composting or soil amending. You can start all over again in the spring with new varieties.
Make sure you look for dahlia bouquets next time you visit the Yakima Farmers’ Market. Check out any of these amazing websites and let the catalogs do the talking. Or better yet, make a trip to a Northwest dahlia farm in September, and pick your plants in person. These three are my favorites.
The Dahlia Barn
13110 446th Ave. S.E., North Bend, Wash.; dahliabarn.com
U-Cut Garden opens Sept. 7.
994 S. Bank Road, Oakville, Wash.;
Visitors always welcome
Swan Island Dahlias
995 N.W. 22nd Ave, Canby, Ore.;
If you haven’t visited yet, put Swan Island on your “bucket list.” It’s the U.S.’s largest and leading dahlia grower with 350 varieties on 40 acres. Cut flowers are available for local pickup, and fields are open to the public through September.
Grow flowers for cutting, to make your own fresh bouquets.
This summer we’re hosting the garden wedding of our youngest son, William. My gardens grew as my children did, and I’ve long dreamed of gorgeous home-grown flowers for fresh bridal bouquets with an abundance left over to decorate every room of the house.
Yet on that wondrous day of days, the display in my perennial beds must be just as lavish and extravagant. How can I have my flowers, and pick them too?
The solution to this delightful dilemma is to plant a separate cutting garden, where I can snip to my heart’s content and not fret about the appearance of the bed when I’m finished. With that in mind, I’m taking over part of my husband’s vegetable garden — but don’t tell him yet. I like to think that I’m growing food for the soul this season, as essential as any vegetable crop. Add some garden-grown flowers to your life: burying your head in a bunch you’ve just picked is an amazing way to begin your day.
Start with a well-drained site that receives full sun. No worries if it’s in a neglected corner or behind the shed; this can be a utilitarian production garden where appearance is not a priority. Or maybe you’d like to create a cutting garden as a feature too spectacular to conceal. In either case, the first consideration must be a convenient water source. Drip irrigation is preferred, but if you must provide overhead irrigation, water early in the day to make your plants less susceptible to disease.
Work in plenty of compost or humus before you plant, along with a few handfuls of time-release fertilizer. This is a garden for just one season, so provide your hard-working plants with all they need to produce a bounty without running out of energy. When the soil warms and the danger of frost passes, it’s time to plant. But some flowers — like sweet peas, larkspur and poppies — have greater hardiness and can be planted as soon as the soil can be worked.
Think like a vegetable gardener and plant in rows that can be easily navigated for snipping, cutting, watering and weeding, or opt for an intensively planted, square-foot gardening scheme that eschews rows. Regardless, deter weed germination in open areas with shredded newspaper, cardboard, organic mulches or other barriers. As your plants begin to grow, mulch them too, but keep the mulch from contacting their growing stems.
Generally annuals are better than perennials for cutting since they tend to bloom profusely over a long season. Certain perennials bloom only once or twice a summer, and it’s wrenching to part with those. By selecting annuals that bloom at different times, it’s possible to have cut flowers from early spring until the first frost. This year, I’m looking exclusively for flowers that peak in early August.
Remember that a variety of flower forms make the most interesting bouquets, so choose a diverse array of flower shapes, textures and fragrances. The point of a cutting garden is to have abundant blooms, so be diligent in removing faded flowers before they go to seed, which signals the plant that the season is over. If your plants come from the garden center with buds, pinch them off before you plant, and do the same with the growing tips of annuals grown from seed. It’s hard to do, but you will be rewarded by bushier, more productive plants before you know it.
These flowers grow quickly from seed and have a long life in a vase or bouquet. Add some sticks, branches, berries or bark to create an unforgettable, one-of-a-kind bouquet.
Amaranthus caudatus ‘Love Lies Bleeding’ This is an heirloom spiller with long, drooping flower spikes that look like chenille ropes. Grow it in green or burgundy. The more you pick, the more this stalwart will provide.
Celosia spicata ‘Flamingo Purple’ Add texture with dark pink, wheat-like flower spikes on long stems that emerge from purple foliage.
Dahlia I already have a dahlia cutting garden, but one can never have enough of these focal flowers. They reliably come into their glory when the weather heats up and don’t stop until frost. Available in a dazzling array of colors and flower forms, plant tubers in early May, stake them with something sturdy, and stand back. I use 6-foot metal fence posts; these big boys mean business and will grow to 5 feet or more, providing you with armloads of bouquet material.
Zinnia One of the longest-lasting cut flowers, zinnias love hot Yakima summers, but resent transplanting. So seed them directly into the garden when it’s warm enough to plant tomatoes. I’ve found packages of single colors like coral, peach, purple, lime green and orange to match our color scheme.
Sempervivum Tuck ‘hens and chicks’ into the corners of your garden, and let them spread and become a living mulch. Attached to a wire stem, they are unique bouquet elements.
Ornamental Karl Foerster Feather Reed Grass (Calamagrostis acutiflora)
Do you yearn for a garden that is more sensitive to our unique Yakima Valley climate and ecology? One that is not chemically dependent and less demanding of water resources (and that most precious commodity of all, your time)? No matter how well planned it was at its conception, every garden will grow to need updating and editing. In the last two decades, an array of ornamental grasses has transformed the American garden. As your garden awakens this month, reevaluate the plants you may have chosen years ago, and consider replacing lackluster, high-maintenance performers with a gorgeous grass.
Calamagrostis acutiflora, ‘Karl Foerster,’ is the most popular ornamental grass in the world, taking its place in local gardens, commercial landscapes and even the planters lining the business district in downtown Yakima. But there is so much more. Ornamental grasses come in all sizes, from ground-huggers to clumpers as tall as towers. They come in many forms, too, from upright tufts to mop-top mounds, to arching fountains. Most grasses will thrive in containers, and some aren’t even green.
Bouteloua gracilis ‘Blonde Ambition’ (Blue Grama Grass)
Its profusion of big, showy chartreuse flowers, held horizontally like flags above the leaves on 2 ½ -3’ stems, is unusual. Extremely cold hardy, ‘Blonde Ambition’ is a new selection of a native North American prairie grass that has been widely used as a drought-tolerant turf substitute in the Southwest and Prairie states.
Carex elata ‘Aurea’ (Bowles Golden Sedge)
In our hot summers, give the 2’ clumps some shade in the afternoon, and keep the soil moist. I think most gardeners will also love Carex morrowii ‘Goldband’ and ‘Variegata,’ since it’s impossible to find a color that these evergreen chartreuse beauties don’t pair well with.
Chasmanthium latifolia (Wild Oat)
Extremely adaptable, this one is happy in both wet and dry shade gardens, yet can thrive in the sun. A finely textured, well-mannered grass that reaches 3’ in height and 2’ in spread, I grow it for its pendulous seedheads, which remain beautiful all winter long, and can be used fresh or dried in arrangements.
Elymus magellanicus (Magellan Wheat Grass)
The first grass I ever planted, this clumper is arguably the bluest of all the grasses and grows to an iridescent 2’ x 2’. Give it adequate water; it’s worth it. This grass remains fairly evergreen. Come spring, I pull out the faded foliage with my hands, rather than cutting the whole plant back.
Hakonechloa macra (Japanese Forest Grass)
This slow-growing creeper has dense cascades of arching, lime-green leaves on stems up to 16” tall that undulate in the slightest breeze. Use it in your shade garden with hosta and heuchera and provide even moisture. ‘Aureola’ is the showy variegated golden form that absolutely glows and may be my current favorite grass.
Miscanthus sinensis (Maiden Grass)
These clumpers produce silvery seed heads late in the season. Forms with fine-textured foliage include ‘Gracillimus,’ ‘Sarabande,’ ‘Graziella’ and ‘Morning Light,’ with white leaf margins. ‘Cabaret’ has cream-colored foliage edged in green; ‘Strictus’ has horizontal bands of yellow on its green foliage. Flame grass, M. ‘Purpurascens,’ grows to 3’ and develops majestic red-orange fall color.
Panicum virgatum (Switchgrass)
This prairie native works in wet or drought conditions and can take full sun or partial shade. It grows narrowly upright, reaching 3’, with nodding panicles of purple in summer that fade to golden. Give it some back-lighting and stand back: the inflorescences absolutely shimmer. I’ve adored ‘Heavy Metal’ with metallic-blue foliage that becomes bright yellow in fall, but when I saw ‘Ruby Ribbons,’ I forgot about every other panicum I had ever seen. With burgundy color that develops early and continues to deepen, it could be a stand-in for the annual Pennisetum setaceum ‘Rubrum.’
Pennisetum (Fountain Grass)
Gracefully mounding and topped by blooms in late summer, check out the array of gorgeous cultivars of P. alopecuroides, such as ‘Hameln,’ ‘Piglet,’ variegated ‘PennStripe,’ and ‘Burgundy Bunny’ with wine-red foliage. P. orientale ‘Karly Rose,’ happy in heat and drought, delights with a heavy bloom of rose-purple all summer.
Stipa tenuissima (Mexican Feather Grass)
Noted to be hardy to Zone 7, my plants have survived two winters in a Zone 6b garden. With a form that soothes and flows, and with silky green blooms in June that become golden at maturity, pick some for a bouquet. Or give it a real job: it can provide good erosion control on difficult slopes. Cut the 1 1/2’ x 1 1/2’ clumps back in the spring.
Purple fountain grass is surrounded by parsley, orange diascia, begonias and marigolds.
The local garden of Linda Knutson and Ron Sell is a good example of how to use herbs. Photo courtesy of Linda Knutson.
Herbs are found in almost every home garden. Traditionally, we expect to find them in manicured beds all their own, or out in a tangle with the vegetables. But why limit these versatile, hard-working plants? Lavishly ornamental, many can hold their own in any area of the landscape.
Planted among your roses, in the front yard parking strip, between trees or shrubs or in the spaces between pavers, these ancient plants add another dimension to your outdoor spaces.
Interplanting like this re-establishes biodiversity in the garden, which is what nature intended. Confound insect pests by layering things they love with things they won’t touch, and attract beneficial insects, birds and butterflies to the garden. If that wasn’t enough, most herbs require minimal care and water once established, and they look amazing in a bouquet.
For example, take an honest look at your rose garden. Despite the extravagant bloom, a rose framework can be angular and prickly, with foliage that suffers in the summer heat. After years of laying nothing more than mulch at the feet of my roses, I’ve added a carpet of fragrant, flowering Nepetas, or catmints, to the bed, creating a billowing petticoat that disguises the bushes’ naturally knobby knees and adds the element of lush informality I’ve been searching for. I can’t get enough of the soft haziness of N. “Walker’s Low” and its taller relative, N. “Souvenir d’Andre Chaudron” — larger flowered and more upright. Their gorgeous violet-blue bloom begins in late spring and will continue until frost if you periodically remove the faded undergrowth.
Working in the herbs is a sensory delight, as your head and hands soak up the fragrant perfume of cut stems and bruised leaves. It’s amazing how quickly a fresh flush of new bloom emerges from the center of these catmints. I use Stachys byzantina — the familiar downy Lambs’ Ears — as a dense ground cover in the roses, inhibiting weed growth and softening sharp angles. Try the superior forms, giant leaved and silver “Helen von Stein” and buttery chartreuse “Primrose Heron,” both of which can be gathered by the armfull for filler in bouquets.
Between perennials and shrubs, and especially among ornamental grasses, add Agastache, or “Hummingbird Mint.” This perennial herb grows in bushy clumps, with upright branching stems topped with spikes of bottle-brush flowers over a long season.
I swoon for anything violet, and the recently introduced A. hybrids, such as “Blue Fortune,” “Black Adder” and “Purple Haze” bloom in my garden into October. With leaves and flowers that smell like anise, they make gorgeous cut flowers and are a magnet not just for hummers but bees and butterflies as well.
For a bright pink or orange color vibe, try A. cana, with flowers that smell like bubble gum or A. rupestris, with hints of licorice. When the plants reach 12 inches in height in the spring, I cut them back by half, which encourages a more bushy form and abundant flower spikes.
As a landscape border, lavender is everywhere, so why not try some of the culinary sages? S. officinalis, and its more colorful forms, “Icterina” or “Purpurescans,” are evergreen sub-shrubs with fabulously pebbled foliage that goes with everything you site next to it. Choose gold margined bright green or steely purple to provide a pop of color and fragrance that will spill over a walkway or edge a border. Chartreuse is a tough color to wear, except if you’re a plant. Santolina “Lime Fizz” is a gorgeous lemon-green form of an old favorite of Beatrix Potter’s Benjamin Bunny. It forms a bun-shaped evergreen mass of delicate fern-like foliage, blanketing itself with the palest of yellow flowers, perfect for picking. Growing to 18 inches, use it with any of the sages.
One of the best low-growing ground covers is creeping thyme. Use it as you would grout between pavers, stepping stones, in the spaces of rock walls or as a lawn substitute in a hot parking strip. It holds up well to foot traffic, doesn’t need very deep rooting and as a bonus it gives off a delicious scent when brushed. Many varieties are available, with green to silver foliage, and with flowers that range from purple to pink to white.
Another beautiful view of Knutson's garden.
Terrariums, like these created by Carol Barany, create tiny gardens indoors during winter. Photo by Robin Beckett.
After spending the last eight months in the garden, I’m coming inside. I’ve mulched and mowed, propagated and pruned. I’ve cried tears of astonishment and inspiration, as well as bewilderment and defeat, in my latest partnership with nature. I’ve practiced sustainable horticulture and integrated pest management, day in, and day out. I’ve created a compost pile large enough to be seen from the moon.
When November comes, I need a breakut like most gardeners, I still crave a daily link to the good green that gives beauty and richness to my life. Come November, I could use some botanical bling, and there’s an easy way to get it: create a terrarium.
A terrarium is a biosphere of any size, from a brandy snifter to a fish aquarium, with a tightly fitting lid. You can even push the boundaries and use an un-lidded glass vessel, if the opening is smaller than the rest of the container.
Inside, compose a landscape in miniature, such as a woodland. Think rainforest, and include plants that thrive on humidity, such as ferns, lichens, mosses or small tropical houseplants. If you are absolutely scrupulous and avoid the slightest overwatering, you can dare to plant succulents in an open terrarium. I have some tender echeverias that spend the summer outside in mixed containers, and they must come in with me when the weather cools. Too gorgeous to tuck away, I showcase my favorites in a large, open glass bowl.
There are endless possibilities. If you spend your days at a desk with a phone and computer for company, add a glass globe containing a few plants mixed with some mementos from your last vacation, like shells or driftwood. Green growing things, close at hand, will sooth and relax you. Terrarium building is a wonderful way to teach children about plants, too, and who is to say you can’t add some tiny dinosaurs or action figures to the mix? Regardless of your style of decorating, a collection of plants flourishing within sparkling glass is always elegant, not only enhancing your home but making a statment about you as a designer.
To make a terrarium, spread a 2-inch layer of ¼-inch gravel on the bottom of the container to serve as a dry well for drainage. Larger stones may be beautiful, but can allow water to collect at the bottom and lead to the need for occasional drainage. If you must use larger stones, place a layer of sheet moss between the soil and gravel to keep water from percolating to the bottom. The moss will also keep the roots of the plants drier and healthier. Regardless, mix some aquarium charcoal into the gravel to filter the water, sweeten the soil, and prevent stagnation and fungi that can grow in a container that lacks a drainage hole.
Now comes the next layer: your favorite sterile potting mix. The thickness of this layer depends on the size of the terrarium and the plants you’re using, but plants in plugs or 3-inch pots should grow well in soil that is 2-3 inches deep. Select an odd number of plants such as three or five, in a variety of leaf shapes and textures. Some should have slender stalks and others should have round and full leaves. For interest, try to vary the color of the foliage. Shop for your plants by placing them side-by-side at the store to see what they will look like in your arrangement. When you plant, make sure only the roots, not the plant stems or crowns, are buried in the soil. Top dress with sheet moss or more pebbles, which act like a blanket and keep the soil from drying out.
Once everything is in place, spray the interior lightly with a mister and put the lid on, if there is one. Place in bright but indirect light, such as a north or east-facing window. Too much direct sun can burn the plants, since solar energy can heat up a terrarium easily. A properly planted and lidded terrarium will maintain a good moisture balance for about three weeks. Condensation on the glass is normal, but if the interior mists up, the planting is too wet, and you should remove the lid for a day. If the mosses or ferns appear too dry, give a light misting and replace the lid. If the container is open, inspect the plants every week or so, and feel the soil. Water whenever it seems dry.
Fill your terrarium with elements from the outdoors. Photo courtesy of Istock.