The Colorado State University (CSU) Trial Gardens attract thousands of visitors to the campus each year. Trial Gardens include the Annual and Perennial Trial Gardens, along with the Plant Select® and Perennial Demonstration Gardens.
Perennial trials evaluate new selections developed and introduced to the rigorous climate conditions of Fort Collins, Colorado. Perennials submitted are evaluated over a period of three summers and two winters. Data collected include flowering attributes, plant uniformity, and tolerance to environmental and biotic stresses. Data collection, garden planting and maintenance are made possible with the assistance of student employees, Extension Master Gardeners, community volunteers and industry supporters. Plant data are collected every other week, from May to early October.
Members of the Perennial Trial subcommittee evaluate the perennial trials June through September rating them on a scale from 0-5, with zero being sick or dying and five demonstrating excellent health and flowering. The seven “Top Performers” are described here.
Brunnera ‘Alexandria’ – TERRA NOVA® Nurseries
Beautiful silver, cordate leaves were very attractive all growing season creating a dependable, bright spot of color in shady areas. Foliage was described as having less veining and being relatively thick. It created a strong mat of silver leaves and provided contrast with other plants such as darker leaved heucheras. During early summer, a delicate cloud of blue flowers creates a unique look in the garden.
Echinacea ‘SunMagic Vintage Fuchsia’ – Flamingo Holland / Bull Breeding
This coneflower was noted for its impressive ‘flower power,’ providing showstopping color for two months. The flowers were a bright and intense fuchsia-pink color, with the ray flowers being held horizontal topped with an intensely colored big “Hershey Kiss cone” on top. The darker cone and dark stems made a great contrast with the bright blooms. Plants had a very uniform growth habit and showed great winter survival.
Eupatorium ‘Little-Pye’ – Dümmen Orange
“Little” is somewhat relative with this native plant. Expect the plant to be ‘little’ and short—at just over a foot tall—for only its first year. Once established, ‘Little-Pye’ can grow and make a statement, reaching upward of 6 feet tall! Place it in the garden where it can fill out and reach for the sky. ‘Little-Pye’ creates a beautiful show in late summer with blooms covering the canopy at its peak. The inflorescences remained attractive after flowering, offering winter interest or potential use as a dried flower. Uniform plants with strong stems held the impressive inflorescences from lodging. The plant was a bee magnet!
Heuchera ‘Big Top Caramel Apple’ – Darwin Perennials
Who doesn’t like caramel apples? This coral bell lives up to its name. Foliage changes color as it matures through the season moving from shades of green—almost Granny Smith apple green—to having hints of red and ultimately overtones of caramel. Contrasting colors on the underside of the leaf—a distinct burgundy color—creates interest. Plants are vigorous and relatively large creating a big canopy—hence the name. Small flowers gave it a more naturalized appearance suggesting use in a woodland garden. Survival through two Colorado winters was perfect. Are you hungry for this plant yet?
Lupinus x ‘Beefeater’ – Gulley Greenhouse and Eason Horticulture Resources
Like the Beefeater guards at the Tower of London, you can’t miss the vibrant colors of this garden classic. The intense, cherry red color that holds up well in the sun with no fading, and the large spires easily make this a “wow” plant from across the garden. This selection bloomed more profusely in full sun and the sheer number of blooms set this plant apart from other lupines. Flower stems were sturdy and without any lodging over the flowering periods. Don’t miss out this one!
Phlox paniculata ‘Ka-Pow® Soft Pink’ – Darwin Perennials
Can one have a perennial border without a phlox? Here’s another great, reliable performer from the ‘Ka-Pow®’ series. Like other selections from the series, ‘Soft Pink’ was noted for its flower power. Flower panicles covered the foliage with a beautiful canopy of soft pink florets with a deeper pink eye, creating an impressive display with a long bloom season. The less than two-foot-tall plants had excellent branching without any pinching necessary. The plant was also resistant to powdery mildew. Consider ‘Ka-Pow® Soft Pink’ to pack a punch in your perennial border!
Sedum ‘Rock ‘N Grow® Back in Black’ – Proven Winners® and Walters Gardens
Crank up the volume with this sedum. Foliage can be so dark at times, it almost appears black. That dark foliage makes a great contrast to the late summer, deep red and cream flower heads. The flowers are a great resource for sustaining pollinators late in the season. The uniform plants are attractive, low maintenance and are a good water-conserving choice for the western garden. During 2023 it tolerated unusually heavy rains and was adaptable to multiple sites. Use it in a border to contrast with the other foliage and flowers. Put some beat into your landscape with ‘Back in Black.’
