2024 Colorado State University Trial Gardens Best Of’s

"The 2024 growing season was more normal this summer than last summer. There were lots of great plants in the trials this summer. The Trial Garden Advisory Committee met on September 13, to review the evaluations from the Annual Evaluation Day, held on August 6, 2024. There were more than 275 attendees for the field day. Thanks to all those who attended, our Trial Garden Advisory Board, and the 2024 summer trial garden employees for another successful year." Shares Ross Shrigley of Plant Select. 

Best of Show
City Lights Purple Dahlia
Selecta One                                                                                                                                                                                                                                          Dahlias are still quite popular with the visitors! A multi-year winner—it is that good! Bred for performance in heat, City Lights Purple lives up to expectations. This award winner flowered through the summer, with rich, deep mulberry-purple flowers with a deep, nearly black center, that are accentuated by the dark green-black foliage, that holds up well in the full sun all season. The bees and other pollinators also loved this plant.

Best New Variety (Grown in Ground)
Karma Caroline Dahlia
Syngenta
A great dahlia for the garden. The clean peachy pink, ~3 to 4” flowers have strong, sturdy stems on 3’ plants that are great as a cut flower! The colors are most intense in cooler temperatures, but even in the warm doldrums of the summer, the colors were still stunning. The nice dark green foliage provided a great back drop to the abundance of flowers. Definitely a multi-purpose dahlia to consider for the landscape!

Best New Variety (Grown in Container)
TerraScape ‘Queen’ Coleus
Kientzler North America
Talk about dramatic! And eye-catching! This vigorous coleus can make a statement in your garden. The deep red maroon leaves with a blaze reddish-pink center, and lime-green shark toothed edges are eye catching! And the colors hold up well in full sun! The plants are sturdy and strong and work well in containers!

Best Novelty
Dianthus JoltTM Pink Magic
PanAmerican Seed
A great performing plant! A dianthus that flowered consistently and profusely through the summer in Colorado! The bright pink flowers with a magenta ring, danced above the clean, dark green foliage. Definitely heat tolerant and one that you should consider for a jolt of color in the summer landscape!

Ground Bed Winners
Coleus Ground Bed (Grown in Sun and Shade)
Ruby Slipper
Ball Flora Plant
A coleus Dorothy would be proud of. This versatile coleus performed well in both sun and shade locations. In the full sun, it sports dark ruby red leaves with narrow, crisp green margins. When grown in shadier conditions, the ruby red leaves sport wider green margins. Sturdy, upright plants with no lodging.

Salvia
Lake Onega Improved
HilverdaFlorist
One of the Salgoon Series salvias; this beautiful dark blue-purple colored salvia has a long flowering period. It started flowering in greenhouse and continued all through the summer with great, sturdy stems and a uniform habit. It handles the heat well and the bees LOVE it.

Verbena
EnduraScapeTM Burgandy
Ball Flora Plant
This is a versatile verbena with a uniform, spreading habit displaying moderate vigor. The attractive color with deep burgundy flowers dotted with a white eye, consistent flowering, compared to others which often have flushes of color. Also attracts some pollinators. This plant can handle high and low temps---all the way down to 19F!

Argyranthemum hybrid
Grandaisy® White Improved
Suntory
This intergeneric hybrid argyranthemum showcased, crisp, white flowers, with a dark yellow brown eye, over vibrant green fern-like foliage. Flowering slowed just a bit with the high heat, but as cooler temperatures returned, flowering picked up. Uniform plants.

Osteospermum
Zion Violet Feather
Selecta One
This African daisy was undoubtedly the best in the bunch. The deep, rich, silky purple flowers were produced all season, even with a couple stretches of extreme heat. The flowers danced just above the foliage medium green foliage on uniform plants. Definitely an osteospermum worthy for the garden or container!

Begonia (Grown in Ground Bed; Sun)
Tophat Rose Bicolor
Syngenta
The Tophat series is a great series and hard to pick just one favorite. Rose Bicolor is the winner this year. It sports nice crisp, glossy green foliage, with large rose and white bicolor flowers. No doubt the plants were floriferous all summer. It was noted this was like a traditional bedding begonia on steroids!

Rudbeckia
SunBeckia® Marilyn
Bull Plant Genetics
It is hard to pick just one of the SunBeckias! Marilyn showed great uniformity, and was floriferous, boasting a long-lasting canopy of flowers on well branched plants. The large, bright sunshine yellow flowers develop a hint of cinnamon brown near the eye as they age, creating a dynamic flower display. Absolutely a hit with pollinators!

Hybrid Impatiens
SunPatiens® Vigorous Purple
Sakata
These bold hybrid impatiens will definitely help fill in a border planting. The large, intense purple flowers are contrasted against the deep green foliage, and will keep flowering, even as temperatures heat up. They are vigorous, with strong branching habit. SunPatiens will certainly
appreciate consistent moisture for maximum size and performance.

Impatiens walleriana (Grown in Ground and Container; Sun and Shade)
Beacon® Bright Red
PanAmerican Seed
This is a versatile plant. It performed very well in full sun! And…does well in shade! Vigorous and great red flower color that holds in the full sun—it doesn’t fade or melt out. Great for massing and filling in the landscape. One of several solid performing selections in the Beacon®
series, which is highly resistant to Impatiens Downy Mildew.

Catharanthus (Vegetatively Propagated)
Soiree® Double Orchid Improved
Suntory
One of several in the Soiree® series that performed well. LOVES the heat! Uniform plants, produced an abundance of silky, lavender colored flowers. The flowers hold up well in the heat and are contrasted by the deep dark green foliage.

Catharanthus (Seed Propagated)
Titan-ium Punch
PanAmerican Seed
This seed Madagascar periwinkle certainly lives up to its name! It packs a punch of solid fruity deep pink to red punch color, all summer long! Nice, large flowers on highly branched plants. As most Catharanthus, it loves the heat! This selection has been bred for high Phytophthora (root
disease) resistance.

Lantana
PassionFruit
Ball Flora Plant
Aptly named—a floriferous lantana for the landscape. The multi-hued dallops of flowers that open a rich yellow, orange, maturing into a crisp clean salmon pink. This spreading lantana is a great mingling plant for the landscape border or mixed container as the ‘filler’ component. It would also work well in hanging baskets. This is a heat loving, drought tolerant plant that attracts lots of pollinators. Definitely a great addition to the summer landscape.

Scaevola
Scala Purple Bird
Dümmen Orange
This fan-flower was definitely a fan-favorite this summer in the trials! It was one of the top selections for both the public and the horticulture professionals. When we mention ‘flower power’, this plant does not hold back! It was a solid patch of deep purple in the landscape all summer. Compact and clean flower and foliage, make this a winner. If we might describe it in one word…”Awesomeness.” Try it out, we are sure you will be a ‘fan’ of this flower!

Geranium Interspecific
Grace Ruby Red (P)
Beekenkamp
What is more classic than a red geranium?! This geranium has vibrant red colored flowers held above the crisp, clean foliage on sturdy stems. The red color holds well in full, blazing sun, with no fading or color melting. Grace Ruby Red has a nice round, mounding habit, that showed little to no Japanese Beetle feeding!

Geranium Zonal
Galaxy Purple
Ball FloraPlant
If you haven’t heard of the Galaxy series, they are kind of out of this world! This year, Galaxy Purple was the top performer. It produces large, sturdy ‘lollipops’ boasting dozens of deep violet purple with a hint of white in the center florets. It consistently produced flowers all season on uniform, well-branched plants!

Dahlia
City Lights Purple
Selecta One
A multi-year winner—it is that good! Bred for performance in heat, City Lights Purple lives up to expectations. Flowering through most of the summer, with rich deep purple flowers, that are accentuated by the dark green-black foliage, holds up well in the full sun all season. The bees and other pollinators also love this plant.

Portulaca
Mojave® Mango
Proven Winners
In this collection of portulacas, Mango was the favorite. The plants were vigorous with a nice low growing form. The copious amounts of mango-orange-colored flowers, with a red center, opened by mid-day, providing waysides for a plethora of bees and pollinators. The whole planting of portulaca was abuzz! Great for massing in the front of the border.

Petunia (Vegetatively Propagated)
Supertunia Mini Vista® Plum Veined
Proven Winners
This petunia performed well all year, from the greenhouse production to the summer landscape. A floriferous plant, with quarter-sized flowers boasting light purple hues and contrasting deep purple-black veins. Although vigorous, the plants played well with their neighbors, not overtaking their space. This is a great massing plant to add impact to the landscape.

Petunia (Seed Propagated)
Easy Wave® Navy Velour
PanAmerican Seed
Another plant in which the name is spot on! The rich, deep purple, that in the right light, looks as though the flowers are made of velvet. The flowers are large and numerous and hold the intensity in the full sun. These are vigorous plants that would work well for use in contrasting other plants and make them pop.

Container Winners
Combination Container
PlaylistTM Uptown Funk
Sakata
This combination of three celosia was stellar in the garden! The container caught peoples’ eyes from across the garden. The vibrant reds, oranges, and yellows provided long-lasting, season long color all the way into fall. The sturdy plants filled out the container well. This combination would work well for fall planter interest!

Rudbeckia
SunBeckia® GraYiti Caramel
Bull Plant Genetics
Who doesn’t love a good caramel candy?! Another award winner from the Bull Plant Genetics SunBeckia lines. This rudbeckia sports a unique caramel flower color, with the outer edges having a warm rich, deep yellow-ish brown color, having a deep reddish-brown eye. As the long-lasting flowers age, these colors develop into a nice overall caramel color. The plants are relatively compact keeping the plants from lodging. Another great Sunbeckia to consider.

Mandevilla
Tropico Unico Pink
Ball FloraPlant
This non-vining type of Mandeville was stellar in the Colorado summer! Large, soft shell- pink flowers, with a rich rose and yellow throat, covered the stems for this containerized planting. The deep glossy green foliage sparkled in the sun. A great upright shrub-like form to definitely
consider for the landscape!

Coleus
TerraScape ‘Queen’
Kientzler North America
Talk about dramatic! This vigorous coleus can make a statement in your garden. The deep red maroon leaves with a blaze reddish-pink center, and lime-green shark-toothed edges are eye catching! And the colors hold up well in full sun! The plants are sturdy and strong and work well in containers!

Geranium
Mojo white
Syngenta
Cloud-like cotton white clusters of flowers float above a deep green foliage. This plant has the mojo with lots of flower power. Best displays when regularly deadheaded. Older flowers not as noticeable, like some other white flowered geraniums. Works well in containers and equally as well in the ground!

Scaevola
Scala Cappello White
Dümmen Orange
Another award-winning fan-flower from the Dümmen group! Cappello White is a smaller statured plant, that works well in smaller containers. It produced crisp, clean, white flowers all summer long! Great planted on it’s own in a container or would be great for use in a mixed container.

Petunia (Vegetatively Propagated)
Tea Flamingo
Beekenkamp
If you want to catch someone’s eyes, plant a couple Tea Flamingo Petunias. This unique, flamingo peachy-salmon colored petunia flowered all summer, well after many other petunias started fizzle. It performed well not only in the container, but in the landscape bed as well. The plants were well branched and have a more outright growth habit. If you’re going to try one petunia, you should try Tea Flamingo. You wouldn’t be disappointed.

Petunia (Seed Propagated)
Easy Wave® Navy Velour
PanAmerican Seed
One of the Easy Wave® series, which all performed well. This versatile petunia also was rated the best for our petunias planted in ground. The large, velvety rich, deep purple, flowers glisten in the bright sun and don’t fade! The vigorous plants fill out containers well and would be a good option for a mixed planter to fill out and spill over the edge. Catch this Wave next year at the garden centers.

Hybrid Impatiens (Grown in Sun)
Sol Luna Light Salmon
Danziger
Sol Luna Prime series by Danziger performed well in the trials this summer. In full blazing sun, surrounded by brick and rock, these interspecific impatiens held their own! Prime Light Salmon was the top rated one in the series with the most uniform growth. The classic New Guinea-like flower sports a delicate peach-salmon color and nearly 2” wide flowers. These are great hybrid impatiens that handle the intense summer sun in Colorado, but versatile for shadier situations as well!

Begonia (Grown in Sun)
Stonehedge Rose Bronze Leaf
Benary
Impressive! Massive! Those were comments overheard from our evaluators. The Stonehedge series can grow to be hedge-like! These seed-grown interspecific hybrid vigorous plants filled out our container well, making a statement. It produced loads and loads of large, bright, rose-pink colored flowers, that were juxtaposed against the deep bronzy-burgundy leaves. The pink-red colored stems echoed the flower colors throughout the plant. They handled the hot, bright sun and heat of the Colorado summer with no problems. If you want to fill in an area in the garden or to make a small annual hedge, definitely consider the Benary Stonehedge Rose

Bronze leaf begonia!
Verbena
Empress® Sun Kiss Pink
Dümmen Orange
Pink. Pink. Pink. This relatively compact growing verbena was stunning with the copious amounts of medium-soft pink flowers that covered the foliage. The flowers aged well, without very little to no browning and fading. It was a showstopper through the whole summer and into
early fall!

Angelonia (Grown in Container/Ground Bed)
Guardian AngelTBlue
Ball FloraPlant
Floriferous is an understatement! This is a stately triploid plant, boasting large, saturated blue, purple-colored flowers. These plants started flowering early summer and flowered all the way until the first frost. This summer snapdragon performed well in both container and ground bed plantings…shooting out of the container like a mid-summer firework!

Lantana
Bandolista Mango
Syngenta
Mango was the best performing Bandolista lantana. With loads of vibrant tropical shades of newly opened yellow flowers to reddish orange older flowers, this lantana provides great hot pop of color in the landscape. One can barely see the foliage when it is in full flower! With its moderate vigor and habit, it works well in containers and hanging baskets, with the ability to tolerate low water inputs. Oh, you’ll be sure to attract pollinators to your garden with this plant!

Calibrachoa
Bloomtastic Serenity 2025
Dümmen Orange
Compared to nearly all the other calibrachoas trialed, Bloomtastic Serenity was covered in two toned light purple with dark purple eye and yellow throat. It bloomed from early summer to very late in the season. When all the other calibrachoa had dwindled with color, Bloomtastic was showy! Overall plant form was great, creating a nice display in the container. This plant definitely lived up to its name!

Portulaca
Mega Pazzaz Fuchsia
Danziger
Overall, the Pazzaz series did well in the trials. Mega was the top scoring selection of the group. The Pazzaz Fuchsia produced bright, intense fuchsia pink-colored flowers on semi trailing stems. We observed that the portulaca in this series was open longer during the day,
opening hours before and after other portulaca had closed. This was a pollinator magnet as well---with so many bees visiting, we could hear the containers humming standing feet away! Great option for container plantings, handling heat and drought conditions.

Begonia Interspecific Hybrid (Grown in Shade; Ground bed/Container)
Megawatt White Green Leaf
PanAmerican Seed
These begonias were developed for both sun and shade conditions. And they perform well in both! The clean white flowers with the bright yellow anthers and pistil contrast nicely with the bright, glossy green foliage. Great vigor in these plants, ideal for container and in ground situations. Pink Megawatt also performed very well in the trials. If you want mega flower energy in the landscape, consider the Megawatts!

Begonia Elatior type
BK Collection Vermillion Red (P)
Beekenkamp
Vermillion Red has been a consistent top performing elatior-type begonia in the gardens! It boasts vibrant red flowers that pop in the part shade. Its upright habit makes it all the easier to enjoy the numerous silky red flowers. Definitely check out this Vermillion Red begonia and the other colors in the series!

Begonia Boliviensis type
Florencio Yellow
Syngenta
The large, soft-butter yellow and bright centered flowers of this Florencio contrast well against the deep, dark green lance-shaped foliage. The plants were very uniform and upright, creating an excellent container display.

Begonia Tuber-type
Adora Velvet Red
Syngenta
Rich, velvety red, quarter sized double flowers abundantly adorned the well branched plants in the trials this year. The mounding type plants filled out the containers well. The crisp, dark green foliage provides a beautiful contrast to the red pops of color.

Interspecific Impatiens (Grown in Shade)
Solarscape® XL Lilac Spark
PanAmerican Seed
The Solarscape interspecific impatiens performed well in both containers and in the landscape beds. XL Lilac Spark produced uniform plants with continuous flowering throughout the season. These seed series hybrids are versatile for the landscape, especially for those that want the traditional New Guinea Impatiens to look for the full sun!

Other Outstanding Varieties
Anigozanthos Kanga® Cherry
Green Fuse® Botanicals
This plant caught the eye of garden visitors this summer. This unique Australian native with velvet like flowers, was eye-catching and provided a rich cherry-red color for weeks on end! The iris-like foliage was attractive, complimenting and filling out the large container. Anigozanthos is
definitely one to look for and consider for your landscape!

Echeveria gibbiflora Coral Reef® Dark Chocolate
Green Fuse® Botanicals
Succulents have been popular for some time. And this Echeveria preformed well. They plants filled out the container nicely. The aptly named plant provided great visual texture. This certainly is a great selection for containers on the patio!

Ageratum hybrid Monarch Magic
Ball FloraPlant
Flowers. Flowers. Flowers. This ageratum performed well in both containers and in the landscape. Unlike old-school ageratum, this one is better suited for full sun. It keeps flowering all season and is a sure fire stop for pollinators, including bees and butterflies!

Helianthus Sunfinity® Double Yellow
Syngenta
The epitome of ‘flower power.’ This vigorous double flowered sunflower boasts rich, 2 to 3” yellow flowers ALL summer and into the fall. This selection is well branching, so just a plant or two can fill a good amount of space in the landscape. If you’re putting it in a container on the patio…make sure to give it a big enough pot! Oh…and Sunfinity Double Yellow---resists the pesky powdery mildew, we all too often see with sunflowers!

Celosia ‘Bright Sparks’ Series
Syngenta
Long lasting, bright colors of deep red, orange, bright yellow, and intense pink can be expected with this series of celosia! The wispy flower heads provide great color all summer, with little fading. Great branching, sturdy stemmed plants that attract pollinators and love the heat of the

Colorado summer!
Agastache Mexicana ‘Summerlong Lemon’
Darwin Perennials
One of several in the Summerlong series, Lemon was a standout in the landscape this summer. This tender perennial started flowering in the greenhouse…and didn’t stop all summer. And it is STILL going! It brings a nice bright spot of color—with lots of pollinator and hummingbird
activity and some fragrance. One certainly would get their money’s worth with this plant in the garden!

Hula Begonias
PanAmerican Seed
These interspecific begonias are quick to fill out in the landscape and in containers. These wax leaf begonia type have a nice trailing and spreading habit that grew to about 12” in the trials and provide lots of flower power! They are versatile, working well as massing plants in the
border, for use in containers and in hanging baskets—in both sun and shade locations!

CSU Annual Trial Winners 2024

Other information about the trials is available here -  flowertrials.colostate.edu.  

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Colorado Waterwise recognizes ALCC CEO for conservation efforts