Field Trials: Field Tested

Jennifer Duffield White

Most growers only get to monitor plant quality in the greenhouse, and occasionally on the retail bench. Yet we all know that its performance at the final destination—be it a container a or garden bed—is what really counts in the end. So while Pack Trials, catalogs and trade shows are great starting points for plant selection, you should consider field trials a crucial tool for helping you pick plants that’ll work best for home gardeners in your region.

With dozens of trials around the U.S., it’s easy to find a trial location that mimics the conditions of your customers’ region. Make time to visit each summer, if you can, but also be sure to check with the trial coordinator for results and summaries of the best performing varieties.

This month, we take a look at a few of the regional trials to find out what made their top lists.

The Gardens at the University of Georgia
A classic trialing location that’s begun to incorporate sustainability into its day-to-day operations, University of Georgia, Athens, tracks plant performance from spring through fall, given a rating of 1 to 5 (five being the best) to each plant every two weeks. This then gets graphed out, so you can see how a plant performs during the season, rather than just an average for the whole season. While some may be fantastic in the spring, they may fade in the heat of a Georgia summer. The great thing is that you can view all of these graphs, along with photos of each plant, at the UGA website, http://ugatrial.hort.uga.edu.

This year’s Best of the Best won’t be announced until November, but here are a few of the varieties that had exceptionally high scores (4.75 or higher) through September 1. We’ve indicated the varieties that scored a perfect 5.0). Be sure to visit the website for updated scores.

They are: acalypha Bourbon Street, Ceylon Lime; alternanthera Brazilian Red Hot, Gail’s Choice, Red Threads; angelonia AngelMist Spreading White, Serena White; begonia Bonita Shea (5.0), Edinburgh (5.0), Anna Feile; Begonia semperflorens Sprint Pink Improved; Bracteantha Mohave Basket Yellow; calibrachoa Aloha Blue Sky, Aloha Tiki Strawberry, Million Bells Apricot, Million Bells Cherry Pink Improved, Million Bells Chiffon (5.0), Million Bells Trailing Yellow, Noa Mega Pink, Noa Ultimate Pink; vinca Cora Deep Lavender, Cora Lavender, Cora Violet, Cora White, Nirvana Pink Blush, Nirvana Red, Nirvana Violet, Pacifica XP Magenta Halo, Pacifica XP White, Sun Devil Extreme Peppermint, Sunstorm Orchid, Sunstorm White with Eye, chrysocephalum Flambe Orange, Flambe Yellow; duranta Gold Edge, Thai Yellow; euphorbia Diamond Frost, Silver Fog; New Guinea impatiens Harmony Snow; Impatiens walleriana Spellbound Scarlet, SunPatiens Vigorous Coral; ipomoea Sidekick Black (5.0); Sidekick Black Heart; osteospermum Crescendo Primrose; geranium Stardom Red, Caliente Coral, Caliente Rose, Allure Hot Coral, Calliope Dark Red, Eclipse Velvet Red, Fantasia Cardinal Red, Fantasia Strawberry Sizzle, Patriot Watermelon, Rocky Mountain Deep Rose 09; ivy geranium Acapulco Compact Cascade Pink, Glacier White; pennisetum Princess; petunia Fortunia Hot Pink, Littletunia Pink, Littletunia Red, Littletunia Red Star, Littletunia Sweet Pink (5.0); MiniMe Dark Purple with Eye, Petitunia Happy Dream (5.0), Supertunia Raspberry Blast, Supertunia Vista Bubblegum, salvia Mystic Spires Blue; scaevola Surdiva White; coleus Henna, Indian Summer, Micanopy, Mint Mocha, Stained Glassworks Daffy, Stained Glassworks Tilt A Whirl; verbena Lanai Bright Pink, Rapunzel Lilac, Tapien Purple; zinnia Profusion Cherry and Profusion Golden.

Dallas Arboretum
Jimmy Turner, director of Horticulture Research at the Dallas Arboretum in Texas, runs an extensive trialing program, testing more than 3,000 varieties each year and giving lots of promotional pushes for the plants that perform well in his gardens.

As you can imagine, Texas summers put plants to the heat tolerant test. The Dallas Arboretum gives the “FlameProof Award” to plants that handle the blistering weather and includes plants such as impatiens Fanfare, torenia Catalina, gomphrena All Around Purple and sweet potato vine Sweetheart.

Jimmy also highlights certain varieties as “Rising Stars.” In 2008, he identified four varieties. Digitalis purpurea Camelot series, a cool-season annual in their region, impressed him, as did cleome Senorita Rosalita, which flowered from late spring, through the heat of summer and into fall. Honors also went to the Cora vinca series, which was the only vinca to survive and flourish under Texas’s phytophthora pressures, and to zinnia Solcito—noted for “incredible disease resistance” and its ability to perform in both high and low humidity, under drought stress, heavy rain and in heat.

You can view photos and past award winners at www.dallasplanttrials.org.

More Texas Winners
Texas trial grounds collaborate for a number of efforts, combining their results to come up with all-star lists for regional growers.

The Texas AgriLife Research and Extension Centers in Overton and Dallas collaborate with the Dallas Arboretum (above) to name outstanding varieties to the North Texas Winner’s Circle Awards. You can view an archive of all of their winners at http://overton.tamu.edu/flowers/ntwc.htm.

And the Coordinated education and Marketing Assistance Program (CEMAP) is a statewide testing program headquartered in Dallas that awards Texas Superstar status to top-performing bedding plants. For 2008, jatropha and Pride of Barbados were their Texas Superstars. In 2009, they’ll be promoting salvia Mystic Spires Blue, graptophyllum Chocolate, thryallis, vinca Cora Burgundy and vinca Nirvana Rose and Pink Blush as varieties that have made the grade in trials throughout the state.

For a complete list of all Texas Superstar plants, past and present, visit http://aggie-horticulture.tamu.edu/cemap/frame.html.

Colorado State University
In Fort Collins, Colorado, the Department of Horticulture and Landscape Architecture, Colorado State University, compiles an impressive list of best performers in all major bedding plant species, along with a few other distinctive awards each year.

For 2008, the Best of Show went to zonal geranium Calliope. The Best New Variety was pennisetum Fireworks, while the best novelty cultivar is a 2009 introduction, ptilotus Joey.

The following varieties also received “best of” recognition for their plant category: angelonia AngelMist Purple; argyranthemum Reflection Pink; bacopa Gulliver Blue Sensation; begonia (wax type) Volumia Pink; calibrachoa Million Bells Cherry Pink Improved; coleus Henna; dahlia Dark Angel Dragon; dianthus Garden Spice Coral; diascia Darla Appleblossom; compact zonal geranium Eclipse Velvet Red; ivy geranium Acapulco Compact Cascade; zonal geranium Calliope; seed impatiens Super Elfin Blue Pearl XP; double impatiens Silhouette Salmon 09; New Guinea impatiens Riviera White Eye; lantana Bandana Pink 09; lobelia Magadi Blue; osteospermum Tradewinds Purple Bicolor; pentas Northern Lights Lavender; double petunia Double Wave Pink; mini spreading petunia Littletunia Red Star; spreading seed-propagated petunia Tidal Wave Hot Pink; spreading vegetative petunia Sanguna Lipstick; rudbeckia Autumn Colors; Salvia splendens Reddy White Surprise; scaevola Surdiva Blue; torenia Moon Golden Improved; verbena Lanai Blue 09; vegetative vinca Nirvana Rose; seed vinca Cora Deep Lavender; zinnia Profusion Knee High Red.

University of Florida
The University of Florida in Gainesville conducts two types of trials each year. They run a winter trial garden to look at winter and spring crops (December through May) for the Florida market, and then they also run a warm-season trial (April through August) that looks at both spring performance and heat and humidity tolerance in the warm summer months.

Twelve cultivars were named award winners for the 2008 Winter Trial: calibrachoa Superbells Dreamsicle; carnation Garden Spice Fuchsia; chrysocephalum Flambe Yellow; delphinium Mistral Star; diascia Wink Pink Improved; erysimum Cirtonia Yellow; erysimum Variegatum; petunia Potunia Pink; snapdragon Solstice Burgundy; viola Penny Deep Blue Improved and Penny Denim Jump-Up; and viola Starry Night.

Like the University of Georgia, the University of Florida gives each variety a rating of 1 to 5 every two weeks and graphs the results so you can see the quality over the entire trialing period. You can view data for each plant trialed at their website: http://hort.ifas.ufl.edu/floriculture/trialgardens/

Kansas State University
Plants that put in multiple years of stellar performance at Kansas State University earn the right to be named part of the Prairie Star collection or the Prairie Bloom collection. Annuals that “grow like crazy and bloom like crazy under lazy gardener care” get grouped into the first category. Annuals and perennials that have shorter bloom times but still exhibit stellar performance fall into the Prairie Bloom collection, based on three to five years of performance at trial sites in Olathe, Wichita, Hays and Colby.

Bedding plants that have earned an addition to the 2009 list of Prairie Stars are: basil Pesto Perpetuo; cleome Senorita Rosalita; dahlia Mystic Illusion; geranium Graffiti Double Red, Graffiti Double Salmon; geranium Caliente Coral Pink, Caliente Rose; New Guinea impatiens Super Sonic Cherry Cream; lantana Luscious Lemonade; ornamental millet Purple Majesty; ornamental pepper Calico, ornamental pepper Purple Flash; pentas Northern Lights Lavender; petunia Baby Duck Yellow, Littletunia Pink, Littletunia Rose, Plush Purple, Plush Salmon, Sun Ray, Shockwave series, Supertunia Cotton Candy, Supertunia Vista Fuchsia; scaevola Whirlwind Blue; verbena Lanai Bright Pink, Lanai Lavender Star, Superbena Burgundy, Superbena Large Lilac Blue.

For a complete list of all of Kansas’ Prairie Star and Prairie Bloom selections over the years, visit www.prairiestarflowers.com.