Earth-Kind Roses

Gaye HammondResidents of Farmer’s Branch, Texas, may not appreciate scientists being purposely mean to roses in their town, but the importance of the National Earth-Kind Rose Research project there is hitting home in a big way. The Guisse Field Watterworth Park houses 400 rose bushes that are part of the National Earth-Kind Rose Research Project – perhaps the largest environmental rose research study of its kind in this country. What visitors to the city do understand is the beauty of this sea of roses with a fragrance that envelopes you from the moment you step into the park.
 
Imagine the amazement when visitors learn these roses have never been sprayed with pesticides or fungicides, have never been fertilized and were only watered three times in 2009.
“This is amazing,” said an awed Kerry Kittrell, visiting the site from Orange, Texas. “If you would have told me a week ago that it is possible to grow roses in a no-maintenance setting, I would have said you are crazy. Never in my wildest dream would I have thought this possible.”
 
The partnership with Texas AgriLife Extension and the Houston Rose Society in this project has been really beneficial to the city and its citizens, said Pam Smith, city landscape manager.
 
“Not only have we been able to reduce our irrigation costs by 65 percent and totally eliminate applications of chemical sprays and fertilizer on the roses in the study, we are redirecting some 600,000 yards of tree trimmings that had been headed for landfills and turned that material into mulch for the planting beds. This project has made it possible and has encouraged us to build four more parks using the Earth-Kind approach to landscape management,” Smith said.

Roses are never sprayed with pesticides or fungicides, they’re not fertilized and receive very little supplemental irrigation in Earth-Kind trials.
The latest Earth-Kind roses
Two more roses have been added to the Earth-Kind program — Cecile Brunner and Reve d’Or. Before receiving the designation, roses go without applications of pesticides, fungicides or fertilizers and greatly reduced supplemental irrigation. Test roses must perform in the unlikeliest of soil conditions — unimproved heavy alkaline clay with a pH as high as 8.0.
 
“That these roses thrive and are beautiful flowering landscape plants even when subjected to our grueling research conditions is a testament to their strong genetic make-up,” said Steve George, horticulture specialist with Texas AgriLife Extension and head of the Earth-Kind rose research. “These roses embody traits that few other roses share – beauty, toughness and easy maintenance – and that has earned them the highest distinction a rose can achieve.”
 
Cecile Brunner is a polyantha shrub-type rose dating back to 1881. It produces waves of light pink clusters of fragrant blossoms having true rose form on bushes that average 4 feet tall and 3 feet wide. While this rose will tolerate some light dappled afternoon shade, it does best in a location that receives eight hours of full direct sunlight each day. It is hardy in USDA Hardiness Zones 5 to 9. (The climbing version of Cecile Brunner did not receive the Earth-Kind designation.)
 
Reve d’Or is “the healthiest yellow rose we have ever tested,” George said. Its name means “Dream of Gold” – an appropriate description for this beautiful repeat-blooming, almost thornless, climbing noisette rose that produces buff yellow semi-double flowers with a fruity fragrance. It has the ability to quickly reach its mature size of 10-18 feet with a spread of approximately 8 feet, but still retains its mannerly habit. It is well-suited for pillars, arbors and landscape structures in Zones 7-9, but grows best in warmer climates.
 
Cecile Brunner and Reve d’Or join Belinda’s Dream, Caldwell Pink, Carefree Beauty, Climbing Pinkie, Ducher, Duchesse de Brabant, Else Poulsen, Georgetown Tea, Knock Out, La Marne, Mme. Antoine Mari, Marie Daly, Mutabilis, New Dawn, Perle d’Or, Sea Foam, Souvenir de St. Anne’s, Spice and The Fairy – bringing the total number of Earth-Kind roses to 21.
 
Reve d'Or is one of the latest Earth-Kind roses“Earth-Kind roses are getting easier for the public to get as growers increase the own-root inventories of these plants,” said Sam Goldwater, owner of Lone Star Nurseries in Tyler, Texas. “These roses are good roses that do well year after year and will perform for the homeowner as they are advertised to do. That is why Lone Star and HEB Grocery Stores have joined forces to make Earth-Kind roses available to shoppers at this grocery chain.”

Earth-Kind research
University of Wisconsin horticulture professor David Zlesak and his colleagues launched the Northern Earth-Kind rose trials in spring 2007. Working under the Earth-Kind umbrella, Zlesak is overseeing the testing of 20 rose cultivars appropriate for USDA Zones 3 and 4 at the University of Minnesota, Iowa State University, Colorado State University, University of Nebraska, Kansas State University and Texas A&M-Commerce to learn how these roses perform in minimal input conditions in the North and other regions of the country.
 
Zlesak and his team are trialing John Cabot, John Davis, Quadra, William Baffin, Brite Eyes, Ramblin’ Red, Alexander Mackenzie, Carefree Beauty, Frontenac, George Vancouver, Lena, Morden Blush, Ole, Polar Joy, Prairie Joy, Sea Foam, Summer Wind, Sunrise Sunset, Sven and Yellow Submarine. Results from this research trial will be announced in 2012.

Black spot resistance
Black spot is the most serious disease of outdoor-grown roses worldwide due to the potential for rapid leaf yellowing and defoliation. Fifty-eight roses, comprising 17 of the 21 Earth-Kind roses and another 41 roses under evaluation in Earth-Kind Research Trials are being challenged with three distinct races of Diplocarpon rosae collected across Eastern North America.
 
“To our knowledge, this is the first widespread screen of rose cultivars using characterized races of D. rosae,” said Zlesak. Test cultivars resistant to all three races of D. rosae include:  Yellow Submarine, Brite Eyes, Blushing Knock Out, Pink Knock Out and Knock Out.
 
“Our hope is that the laboratory data will be an efficient predictive tool to help identify roses with durable disease resistance in the landscape,” Zlesak said.
 
As work under the Earth-Kind umbrella continues, both in the South through Texas AgriLife Extension and through their collaborators at universities across the country, nursery growers and landscape professionals are realizing tremendous benefits. Earth-Kind research is making it possible for these professionals to offer their customers a complete landscaping package of products and plant materials that are backed by years of rigorous scientific research and a proven track record of top performance regardless of environmental influences. Earth-Kind research is what separates good plants from exceptional plants for the landscape.