Allium ‘Summer Beauty’ from Stonehouse Nursery, LLC
Soft lavender-blue flowers were prolific and brought strong flower power later in the summer. Flowers were relatively tall and held above the foliage for maximum show but had good structure and did not lodge. The plants were uniform and very attractive with glossy, green flat leaf blades.
Echinacea ‘Sombrero Tres Amigos’ from Darwin Perennials
The flowers were unique with an “evolution of color” that resulted in three different shades of color during the season. Blooms were vibrant with a rich saturated color. Abundant flowers remained in bloom for a long time and created an impressive overall show. Plants had a good growth habit with strong branching and no disease.
Penstemon ‘Dakota Burgundy’ from Terra Nova Nurseries
The dark burgundy foliage was a key reason for the superior rating. Multiple shades of burgundy added interest to the dark foliage and help make the white/lavender flower color really stand out. Blooms are very prolific with a long flowering period. It was noted by evaluators that although the flowers are very impressive, the plant looks very showy even when not in flower due to the attractive dark foliage that remained clean all season and never had got “floppy ear.” Plants were very reliable and had 100% survival over three seasons.
Phlox Ka-Pow series from Darwin Perennials
Evaluators were impressed with the entire series as all had similar height, were very uniform, and resistant to powdery mildew. Flowers had a long period of bloom with no color fade. The series had a range of colors that went from soft lavender to a vibrant pink. The pink entry was noted to have some shades of coral which is unique to Phlox.
Salvia ‘Blue by You’ from Darwin Perennials
Vibrant blue flowers were very showy with prolific amounts of blooms early in the season and an impressive repeat later in the season after a hard cut back of old blooms. The unique blue color is a great addition to the pallet of Salvia colors in the trade and evaluators said they “had to go see it” from across the garden.
Colorado State University has announced the top performers in its three-season trial garden in Fort Collins, CO.
Researchers use the trial garden to evaluate new perennial plant species and cultivars in Rocky Mountain environmental conditions. Plants are evaluated for their vigor, uniformity, floriferousness, and tolerance to biotic and ecological stresses.
The garden is paid for by plant companies that pay fees to enter their plants into the trials. The garden relies on students and volunteers to maintain it and draws thousands of visitors every year.
The research is valuable to both industry and home growers. The Rocky Mountain climate has unique needs with its high altitude, intense solar radiation, drying winds, severe hailstorms, large fluctuations between day and night temperatures, and a season-long need for irrigation.
Testing and Scoring
The plants go through three summers and two winters before being swapped out for the next variety. Each member of the perennial trial subcommittee is required to do a write-up on each perennial for the months of June, July, August, and September. Plants are scored on a scale from zero to five on how well they survive in the Rocky Mountain climate.
- Dead or no flowers
- Poor: Plants are sick or dying
- Below Average: Plants are unattractive, i.e., plants are leggy, chlorotic, or have few flowers
- Average: Plant appearance with growth characteristics expected for the season. Few flowers but are uniform
- Good: Plants look attractive, and flowers are strong
- Excellent: Plants are very healthy and uniform with impressive flowers
Top Five Performers
After the data from all the members is compiled and members of the committee have met to discuss and review photos of each plant, the committee votes on the top performers.
The top performers for the 2020 Perennial Trials are:
- Allium ‘Summer Beauty’ from Stonehouse Nursery, LLC
- Echinacea ‘Sombrero Tres Amigos’ from Darwin Perennials
- Penstemon ‘Dakota Burgundy’ from Terra Nova Nurseries
- Phlox Ka-Pow series from Darwin Perennials
- Salvia ‘Blue by You’ from Darwin Perennials
Johnny Eppich is a former Digital Content Editor for GreenhouseGrower.com and GrowingProduce.com.
See all author stories here.