Posted by Dr. Jim Klett, Department of Horticulture and Landscape Architecture
The results are in and we are excited to announce the 2018 "Top Performer" Perennials! Winners of the "Top Performer" award are selected by a different process than the "Best Of" Annual winners. Since individual perennials often peak at different times of the year, evaluators meet and review photos taken every two weeks during the growing season for the entire trial period of two winters and three growing seasons. Data tabulated by the student coordinator throughout the season is also taken into consideration during the process. The evaluators are members from the Perennial Trial Garden sub-committee which is made up of professionals from the local Green Industry as well as staff from Colorado State University. A perennial entry is only considered for the "Top Performer" award if it has maintained superior performance in the ground for two winters and three growing seasons.
Geum ‘RUSTICO™ Orange’ from Terra Nova® Nurseries
(Geum x ‘TNGEURO’PP28238)
Flowers were a beautiful bright orange and very prolific but the foliage was equally impressive if not more so and some evaluators commented the plant “looked so good that it didn’t even need the flowers”. Plants had a great dark green foliage that kept a fresh look all through the season and made a good contrast for the colorful blooms. The growth habit was very controlled and had a very uniform appearance. It would make a great choice for mass plantings.
Phlox Flame® New Improved Purple from Dummen Orange®
(Phlox paniculata Flame® New Improved Purple)
Abundant purple flowers made a solid canopy of color at peak bloom and also rated higher than other phlox for an impressively long bloom period. Plants had a very uniform growth habit with dark green foliage. A small splash of white at the base of each petal added a bit of “sparkle” to each flower as it matured. Blooms also were noted to have an attractive color even as they faded late in season. Plants had superior resistance to powdery mildew. 
KISMET™ Raspberry Coneflower from Terra Nova® Nurseries
(Echinacea 'TNECHKR'PP28768)
Prolific flowers formed a solid canopy of blooms over the plants and even had an attractive rustic look as it faded from peak bloom. Dark green foliage kept the plant attractive even at times when the flowers were not present. Plants had a very uniform growth habit and good branching. The KISMET™ series also features colors of orange, red and yellow.
Plants were unique with a relatively small, compact mounded growth habit but packed a lot of flower power on the top of each one. Flowers were very showy and predominately red but had an edge of yellow around the tip of each blossom. Plants had attractive green foliage that complemented the bloom color. Cold hardiness was also very impressive as the survival rate was very good for a Gaillardia. Additional entries in the ‘SpinTop’ series seemed to have superior cold hardiness as well.
Delosperma ‘Alan’s Apricot’ from Plant Select
(Delosperma ‘Alan’s Apricot’PPAF)
Flowers made this a standout for both the unique color and continual blooming through the season. At peak bloom plants are just a carpet of Apricot colored flowers. Plants are very uniform, have great vigor and have better cold hardiness than most Delosperma . Good for low water plantings but will also tolerate extra water in areas that often kills other Delosperma. This is a great low maintenance plant.
