Colorado State University Announces 2017 “Top Performing Perennials”

Posted by James E. Klett, 

Department of Horticulture and Landscape Architecture, Colorado State University

The following six perennials were recently selected by the Perennial Trial Garden sub-committee as being superior after 3 years of growth and winters.  Plan to utilize these in your designs and home gardens in 2018. I think you will be happy with the results.

Kahori® Border Pink from Bartels

(Dianthus ‘Kahori’)

Noted as an impressive advancement in breeding, evaluators described this as the new standard for Dianthus.  The vibrant pink flowers cover the plants at peak bloom and create a mat of stunning color.  This entry is superior for an extremely long period of bloom and exceptional uniformity.  It has proven to be reliably winter hardy and would look great in a rock garden or crevice garden.  It looks great in ground beds and would make a beautiful border, but is a great choice to use in containers since it is always in bloom.  This selection remains very compact and has great heat tolerance during the peak of summer temperatures.  It was very attractive even during its first year in the garden and has only gotten better each year since it was planted.

Winterbells® Helleborus from Hilverdakooij

(Helleborus Interspecific 'JWLS')

This winner was selected in part for its unique ability to bloom over the entire spring and summer.  It adds a touch of elegance to the garden with delicate nodding bells, glossy dark green foliage and a very attractive dense, compact growth habit.  Narrow, graceful foliage can be evergreen if planted in a protected location and is relatively low maintenance.  The subtly beautiful bell shaped flowers provide a long season of interest as they emerge a dusty pink, becoming pale yellow, white, and then light green by summer.  Besides making a great groundcover, the flowers are useful for cut flower production throughout the year.

 

 PHENOMENAL™ Lavender from Cultivaris

(Lavandula x intermedia ‘Niko’^PP24193)

The abundant, tall graceful flower stalks are held high above the foliage for maximum display.  Besides being very uniform, all plants had excellent cold hardiness.  It was noted that they would do best if grown on the drier side to avoid lodging of the flower stalks.  Pollinators are very attracted to this plant and it has a high oil content that makes is very attractive to commercial production as well as providing the classic lavender fragrance to the garden.

 

Flame® Blue Phlox from Bartels

(Phlox paniculata Flame^® Blue)

Abundant blue and white flowers are held upright on sturdy stems that never lodged despite overhead irrigation used in the garden.  Flower color is a subtle blue that is strongest in early summer and again late in the season as the temperature cools.  It was a relatively early bloomer starting in mid-July and could continue through October if deadheaded.  Self-branching plants had a very full and uniform growth habit as well as superior resistance to powdery mildew.

 

 

Ronica™ Dark Pink Veronica from Danziger

(Veronica Ronica™ Dark Pink)

Big, fat and sassy flower spikes put on an eye-catching show of vibrant pink flowers.  Plants keep a very formal appearance with great uniformity and glossy emerald green foliage that really sets off the pink flowers.  Bloom period was very long especially if deadheaded.  Had superior resistance to powdery mildew compared to other entries growing in the trial.  Growth habit was very full and dense.

 

Class of 2016 - “Too Good to Wait” Award

The Perennial Trial Garden Sub-committee likes to award the ‘Top Performer’ designation to superior plants that have been in the ground 2 winters and 3 growing seasons. This category is to acknowledge an upcoming plant that has been in the ground one winter and two growing seasons and shows excellent performance thus far in the trial. The following plant impressed the Perennial Trial Garden Sub-committee so much that they designated the category name: “Too Good to Wait Performer”.

 

KISMET™ Intense Orange Coneflower from Terra Nova Nurseries

(Echinacea 'TNECHKIO'^PPAF)

The sheer mass of vibrant flowers draws people all the way from across the street.  Prolific flowers form a solid canopy of blooms over the plants which makes this variety a great choice for the home gardener or landscaper looking for a showstopper.  The intense orange color almost seems to glow at its peak.  Flower color fades to an attractive shade of pale yellow to maintain a long season of bloom.  Foliage is also very unique and attractive early in the season.  Plants have a very uniform growth habit and good branching.  The KISMET™ series also features colors of raspberry, red and yellow.