THE TRICKS TO KEEPING A FLOWER ARRANGEMENT GORGEOUS FOR AS LONG AS POSSIBLE

Pretty petals and vases are just the beginning—especially when it comes to fending off bacteria.

Bringing flowers home from the shop or plucking them from your garden is just the first step in keeping them fresh and lovely in your home. But taking care of a floral arrangement is more than just filling up a pretty bowl with water. You’ve got to care for your plants by protecting them from bacterial growth and wilting through a step called conditioning.

Luckily, you don’t need to be an expert florist to make your bouquets last as long as possible—and in some cases, all you’ll need is a cotton ball or a teaspoon of sugar. Cultivated: The Elements of Floral Style, out last week, provides the perfect guide to arranging and maintaining your blooms, and some gorgeous photos for inspiration.

The following is an excerpt adapted from Cultivated: The Elements of Floral Style by Christin Geall.

Conditioning Flowers

Cultivated provides the perfect guide to arranging and maintaining your blooms, and some gorgeous photos for inspiration.

The professional term for postharvest care of flowers is conditioning. In commercial applications, conditioning usually involves a clean cut once the flowers have come in from the field and a resting period in water to which a chemical hydrator and/or a nutrient-based product have been added to encourage flower development. Often an antibacterial agent is used, as well.

The principles of conditioning are important to understand, whether you grow your own flowers or purchase them. If your flowers have been conditioned properly, they won’t wilt when you bring them indoors, nor be half as thirsty in the vase. However, every type of flower has unique tastes and predilections, so I’ll start with some basic principles and get more specific as we go. Clean water is of the utmost importance. Tepid is better than cold.

When you come home from the shop or in from the garden, strip the lower leaves from stems. Leaves continue to transpire (give off water vapor) after a flower has been cut, so keep only those necessary to your work. In some cases, such as with lilacs, it’s best to remove them all.

Different types of flower stems should be treated differently at this stage. The British Florist Association has a handy guide online covering hearty stems, hollow stems, woody ones, milky ones, and so on. Generally speaking, hollow stems (such of those of delphiniums) should be filled with water and plugged using a cotton ball and an elastic. Lupines and amaryllises also have hollow stems and heavy heads, so it’s wise to support the flower with a prop. Floral maven Sarah Raven recommends using bamboo cane (I’ve used barbecue skewers too), as an insert. Fill the stem with water, place the support inside, trim it to length, and then stuff cotton wool into the hole. Wrap an elastic around the base to hold the whole thing together. Although this might seem tiresome, you’ll be thankful you did it.

If you are using woody stems, slit them, score them with an x, or smash them with a hammer at their base to allow the stems to absorb more water. Shrubs, blossoming branches, chrysanthemums, and roses all qualify as woody. The stems of spring bulbs like tulips and hyacinths may have a white portion that doesn’t absorb water, so trim this off. Narcissi (daffodils) exude a slimy sap after cutting. Change the water repeatedly before arranging.

Many soft-stemmed plants benefit from a hot-water dip. This method damages the cell walls of stems and allows the cut flower to take up water. Dip about 10 percent of the stem length for about twenty seconds in freshly boiled water, being careful not to steam yourself or the flower. I keep an electric kettle in my studio for opium poppies, Cerinthe, and euphorbias. You can try this method with wilted roses, too, adding a teaspoon of sugar to the water they rest in after searing. In a few hours, they may revive.

Another method for quickly treating sappy stems is to burn them. This damages the stem so it can absorb water and also seals it off, preventing wilting. If I have a small number of Icelandic poppies, I’ll simply sear the stems with a barbecue lighter. Flower farmers use propane blowtorches. Just run the flame along the lower portion of the stem until it goes semi-transparent and the sap bubbles and burns a bit at the cut end of the stem.

Foliage can be revived just as you might lettuce for a salad. Place the leaves in a cool bath, then shake off excess water and store them at a low temperature to perk.

After whatever special treatment you’ve doled out (the requirements of each type of flower can be a bit intimidating, but you learn them over time), leave your flowers to rest in deep water, in a cool place away from direct sunlight. Try to leave them for a few hours or overnight before arranging.

Carefully top up your vessel with water after arranging; use a small watering can for fitting in between stems. Remember to keep your arrangement away from sun and heat.

Keeping Flowers Fresh

Every living thing carries a microbiome, flowers included. In vase water, bacteria propagate, feeding off their primary food source—the cut ends of stems. The stems degrade eventually (giving old vase water that special swampy stench), but before that point the bacteria clog your plant’s stem capillaries, preventing them from taking up water and shortening the vase life of your flowers. This is why freshly cutting stems is often recommended to prolong the life of flowers.

I religiously change water daily and advise my customers to do the same. If the water can’t be poured out easily, just run fresh water into the flowers to flush. Additives can also help. Sarah Raven advises, “What cut flowers need is a balance of sugars that can be utilized for metabolism, a substance to raise the acidity of the water and an antibacterial agent. Commercial sachets of cut-flower food contain agents for all three.”

If you don’t have “flower powder” or if you eschew plastic packages or those mysterious substances known as “agents,” you can, as Raven suggests, improvise with a teaspoon of sugar and a couple drops of bleach. I’ve also heard vodka can work to slow the growth of bacteria.

If I seem reluctant to advocate specific products or potions, it’s because each type of flower has its own response to various substances (astilbes, aye to alcohol; Asclepias, yea to sugar), and the level of detail involved in itemizing who loves what could crush your enthusiasm. If, however, you’re one of those conscientious people who like to be armed with all the facts, seek out “Conditioning Flowers,” a wonderful flower-by-flower online list of management and care compiled by the garden club of Brookfield, Connecticut. Sarah Raven also offers detailed advice in her now-classic 1996 book “The Cutting Garden”. 

Excerpted from Cultivated by Christin Geall, published by Princeton Architectural Press.

Announcing the 2020 GCA Plant of the Year

The 2020 Freeman Medal winner Geum triflorum, A Stellar North American Native Plant

Geum triflorum, commonly known as prairie smoke, has been named the 2020 Plant of the Year by The Garden Club of America (GCA). Annually, the GCA identifies a stellar North American native plant to receive The Montine McDaniel Freeman Medal: Plant of the Year. 

Prairie smoke, an exquisite herbaceous perennial, is an early bloomer on prairies and a great nectar source for native long-tongued bees and butterflies, as well as native bumblebees and sweat bees. Although prairie smoke is being challenged by taller, non-native plants in its native mesic prairie sites, it is readily adaptable to many other areas. Tolerant of poor soil, moderate drought, heat, and humidity, Geum triflorum can be grown in sun or partial shade and is suitable for cottage gardens, prairies, meadows, and perennial beds. It is not favored by deer or burrowing animals. Geum triflorum is hardy in USDA Hardiness Zones 3-7.

This medal was established in 1995 to highlight underutilized, but highly worthy, native trees, shrubs, groundcovers, vines, and perennials. The goal is to draw attention to select native plants, encourage their use in the landscape, and make them familiar to gardeners and more available in nurseries. The annual medal selection is carried out by a group of highly respected horticulturists from across the country. Woody and herbaceous plants are nominated in alternate years. The 2020 winners were selected from 23 herbaceous plants nominated by members of GCA clubs.          

Honorable Mention was awarded to Asarum canadense, wild ginger. This North American wild ginger, a shade-loving herbaceous perennial, colonizes to form a graceful ground cover that successfully competes with non-native plants. It is a food source for Battus philenor, pipevine swallowtail, is deer resistant, and unpalatable to other mammals. A low maintenance plant, it grows well in many different soil types. Asarum canadense is hardy in USDA Hardiness Zones 4-6. 

Honorable Mention was also awarded to Penstemon strictus, Rocky Mountain penstemon. This native penstemon is a prolific pollinator magnet, attracting butterflies, moths, and native bees. It is adaptable to both wild sites and garden settings and thrives in sandy loam, rocky soil, and even clay soil. Penstemon strictus is a vigorous, low maintenance perennial suitable for growing in sun or partial shade. Penstemon strictus is hardy in USDA Hardiness Zones 3-8.

Special Recognition was awarded to Zamia integrifolia, coontie, a native of the southeastern United States (GA and FL) and parts of the West Indies. Z. integrifolia is the only cycad native to the United States. Coontie was harvested almost to extinction during WWI, because its starchy roots were made into a mold-resistant flour that was sent overseas. Along with its comeback came the rediscovery of Eumaeus atala, Atala butterfly, which uses coontie as its host plant. Zamia integrifolia is hardy in USDA Hardiness Zones 8-11.

2020 PHS Gold Medal Plants Announced

The Pennsylvania Horticultural Society has selected the 2020 Gold Medal Plants, recognizing exceptional plants for both home gardeners and professional landscapers. The PHS Gold Medal Plant Program spotlights outstanding trees, shrubs, vines, and perennials for gardens in the mid-Atlantic region (growing zones 5 to 7). Plants are chosen for their beauty, hardiness, and ecological benefits.

“PHS has incorporated these plants in many of the gardens and landscapes that we manage and can recommend them as reliable plants for our region’s growing conditions. Many promote pollinators and birds in the garden and are deer resistant,” said Julia Thomé, Director of Gardener Engagement at PHS. “A selection of Gold Medal Plants will be on display at the 2020 Flower Show, and PHS staff and volunteers are available to talk with you about these and other plant choices for the home garden.”

Since 1979, the Gold Medal Plant program has honored and promoted plants of outstanding merit. The program was originally conceived by noted nurseryman Dr. J. Franklin Styer, who realized homeowners and gardeners needed to learn about superior woody plants for their landscapes. Five years ago, PHS began including perennial plants in addition to woody plants, in its selections. Plants are nominated from submissions by home gardeners, garden designers, horticulturists, landscape architects, nursery owners, and propagators.

Once nominated, plants are reviewed by a committee of expert horticulturists led by Chairman Steve Mostardi of Mostardi Nursery. Through in-person discussions and an online rating system, the Gold Medal Plant Committee selects the winning plants, on a yearly basis, that meet the rigorous criteria for excellence set forth by PHS. Gardeners who acquire a Gold Medal designated plant can be assured the plant will exhibit standards of excellence for pest and disease resistance, as well as ease of growing when planted and maintained appropriately. To view a searchable database of all past and present winners, please visit phsonline.org/programs/gold-medal-plants/.

2020 PHS Gold Medal Plants
Aronia melanocarpa “Viking” | Black Chokeberry
Flowers bloom in spring, followed by showy black fruits and red fall foliage. Fruits are edible when cooked into jams, salsa, or baked goods. Plant in combination with Virginia bluebells, Bowman’s root and/or short-toothed mountain mint. Can be planted in mass as a screen. Deciduous shrub; height 3-6’; zones 3-8.

Carpinus caroliniana | American Hornbeam (aka Ironwood, Musclewood)
Small size understory tree, ideal for residential sites. Catkins in March give way to yellow nutlets in late summer. Yellow-orange fall foliage. Steel gray bark provides winter interest. Plant in combination with native viburnums, grasses, and/or sedges. Deciduous tree; height 20-30’; slow growing, zones 3-9.

Coreopsis verticillata ‘Zagreb’ | Threadleaf Coreopsis
Bright yellow flowers, compact and upright, easy to grow in-ground or containers. Reblooms if sheared mid-summer. Great in combination with evergreen shrubs, Little Bluestem ornamental grass, native butterfly weed, and/or veronica. Herbaceous perennial; height 12-18”; zones 3-9.

Geranium X cantabrigiense ‘Biokovo’ | Cranesbill Geranium
Low growing and compact; will spread slowly as a groundcover. White flowers tinged with pink in spring. Plant in combination with a variety of bulbs such as daffodils or Allium ‘Summer Beauty,’ lady’s mantle, and/or fall blooming toad lilies. Herbaceous perennial; height 10-12”; zones 5-8.

Hydrangea arborescens ‘Haas’ Halo’ | Smooth Hydrangea
Large lacecap flowers, blue-green foliage. Spent flowers provide winter interest. Drought resistant once established. Plant in combination with the ninebark shrubs, Siberian bugloss, leadwort, Jacob’s ladder, smooth aster and/or reed grass. Deciduous, woody shrub; height approx. 4’; zones 3-9.

Perovskia atriplicifolia ‘Little Spire’ | Russian Sage, Little Spire
Compact and erect sub-shrub, drought tolerant. Striking light blue to violet color flowers. Aromatic silvery foliage. Great in combination with purple coneflowers, phlox ‘Jeana,’ sneezeweed, betony, and/or Foerster’s feather reed grass. Woody perennial; height 2-3’; zones 5-9.

Come Out of Your Cave; The winter garden is full of promise and productivity.

Once the usual fall garden tasks are addressed — leaf raking, bulb planting, clearing of spent annuals — the yard warrior and avid gardener alike retreat indoors for the long winter. Take a moment to read this article written by Adrian Higgins in the Washington Post this week about the period between now and March that offers a chance to take charge of the garden outside the demands of the growing season in a productively unhurried way.