Roses continue to be among the most popular flowering plants in Louisiana landscapes, and the LSU AgCenter is expanding its rose research and demonstration trials at the AgCenter Hammond Research Station and the AgCenter Botanical Gardens at Burden.
Leading the rose trials are two new national rose evaluation programs sponsored by the American Garden Rose Selections and the American Rose Trials for Sustainability, said AgCenter horticulturist Allen Owings. “The last winner in this program was named in 2014, and the first winners in the new AGRS program will be official in 2016,” Owings said.
The model employs a long-used rose trialing method from Germany. It includes disease resistance, hardiness, attractiveness and habit, and roses are not treated with any chemical pesticides in the evaluations. The motto of this new program is “bringing you great roses you can grow where you live,” Owings said.
The LSU AgCenter Botanic Gardens at Burden is one of 12 initial AGRS trial sites in the country. The U.S. selection program will include regional winners from the Northeast, Southeast, North Central, South Central, Northwest and Southwest. The program uses regional evaluation and testing under low-input conditions to identify the most disease- and pest-resistant, hardiest and best garden-worthy rose varieties.
The AgCenter is also evaluating Kordes rose varieties for the Gulf South. Kordes is one of the world’s largest and oldest rose-breeding companies, Owings said. They do not use fungicides in rose development and evaluations.
“Disease resistance in hybrid teas, sustainability in rose growing and growing ‘own-root’ modern roses can be achieved with some of these varieties,” said Wanda Ellis, research associate at the Botanical Gardens at Burden. “Well-known older Kordes varieties that we have successfully grown in Louisiana many years include Shreveport and Iceberg.”
Some of the newest Kordes hybrid tea and floribunda rose varieties being evaluated at the AgCenter Hammond Research Station and at the Botanical Gardens at Burden include Beverly, Grand Amore, Pink Enchantment, Sunny Sky, Wedding Bells, Winter Sun, Poseidon and Summer Sun.
David Austin English roses are crosses between modern and old garden varieties. “They have the profuse flowering of modern roses along with the fragrance and disease resistance of older garden roses, and they continue to be popular with some gardeners,” Owings said.
A new three-year trial started in 2014 includes observations of factors such as flowering, plant size, flowering cycles, leaf spot susceptibility, blackspot susceptibility and more to determine the best of these roses for south Louisiana.