2017 trial garden results

Trial garden managers from throughout the United States share their top annual and perennial picks.

This year, several garden managers submitted their best-in-show annuals and perennials for our 2017 Plant Trials report. Descriptions of all varieties were submitted by their respective trial garden managers.

Best drought-tolerant annual

Alternanthera hybrid ‘Plum Dandy’ (Proven Winners), North Carolina State University

‘Plum Dandy’ got better and better as the season went along. This groundcover is grown for its gorgeous rich purple foliage. Each plant forms a nice carpet that fills in a space approximately 3 feet wide by 2 feet.

Alternanthera Purple Prince (PanAmerican Seed), The Gardens at Ball

A durable carpet of ruby/burgundy foliage that was ready to take on any summer condition, including drought and rain. Alternanthera Purple Prince provides a unique color accent in the landscape, containers, or in mixed high-impact combos. It’s low-maintenance for professionals and home gardeners alike.

Angelonia Archangel Blue Bicolor (Ball FloraPlant), Young’s Plant Farm

We had a great combination in our garden this summer with angelonia Blue Bicolor and vinca Valiant Punch (PanAmerican Seed). Both genera are well known for their drought tolerance and the new bicolor variety of Archangel angelonia does not disappoint!

Begonia ‘Whopper Improved’ series (Benary), Iowa State University

This series starts blooming in early summer and shines on through the season covered in blooms. Even in full sun, these begonias can go days without water without dropping flowers or foliage.

Pennisetum glaucum Copper Prince (PanAmerican Seed), South Dakota State University

This plant was transplanted to a full sun site from the greenhouse. It was given an average rating of 4.6/5.0. Plants have many tillers giving them a very full look. New foliage has a golden color tinged in red with older stems developing a bronze red color. Very floriferous with a continual progression of new flower heads developing. Foliage ranges in color from green to coppery-burgundy. Plants are extremely uniform in size and flowering. Each plant has nearly a dozen flower spikes with additional new flower spikes developing. The foliage has remained a coppery green color all season long.

Pentas Graffiti Lipstick (Benary), Mississippi State University

The Graffiti series performs well under our hot, humid summer conditions, with Lipstick providing more top scores than any other color during the season.

Portulaca ‘Colorblast Double Magenta’ (Westhoff), Dallas Arboretum and Botanical Garden
Portulaca Pazzaz Nano (Danziger), Mast Young Plants

This new series from Danziger has large, brightly colored flowers that open early in the day. Nanos are more compact than the original Pazzaz series, and can be finished with little to no PGR.

Portulaca Pazzaz Nano (Danziger), Plantpeddler

This plant will tolerate just about any stress test you give it. Hot and dry to full wilt, it takes it all and stays in good color. A great portulaca series that will have open flowers earlier in the morning and will stay open later in the evening. If you need a plant in a hot, dry spot, this is the series to plant.

Best drought-tolerant perennial

Agastache ‘Morello’ (Terra Nova Nurseries), North Carolina State University

‘Morello’ has dense, showy, deep pink colored flowers that the bees love. Our 100 degree-plus days didn’t keep this showstopper from flowering.

Echinacea Cheyenne Spirit (photo included in another section) (Kieft Seed), The Gardens at Ball

Well-established landscape coneflower. Held its incredible colors all summer. This All-America Selections Winner features high-demand prairie colors to the garden. The incredibly vibrant segregating mix delivers maximum flower power with superior garden performance. Plants are shorter, better branched, and fuller than tissue-culture varieties.

Echinacea Lakota Santa Fe (above) (Proven Winners), Walters Gardens

We’ve been looking for easy-to-grow echinacea for years and one of the best that we’ve found is ‘Santa Fe’. Since it’s from seed, it has slight variation in color, but it’s mostly in the red-orange color range. We’ve been pleased by both its container and landscape performance, and it’s been great on a liner production level as well.

Delosperma Delmara Orange (Green Fuse Botanicals), Mast Young Plants

This first-year flowering perennial had significantly larger flowers and a heftier habit than other delosperma we have tried.

Salvia Mystic Spires Improved (above) (Ball FloraPlant), Dallas Arboretum and Botanical Garden
Perovskia ‘CrazyBlue’ (Darwin Perennials), The Gardens at Ball

Unique interlacing branches with deep blue flowers. Looked good all season through all weather. ‘CrazyBlue’ is deer resistant, as well. It holds up in the landscape or in large containers as a tall accent plant. Very hardy (Zone 4).

Best heat-tolerant annual

Alternanthera ‘Plum Dandy’ (Proven Winners), Dallas Arboretum and Botanical Garden
Bandana Red Lantana (Syngenta Flowers), Plantpeddler

Heat-loving plant that performs at its best when the weather is at its worse. Full mass of red flower clusters that continue to flower until frost. Has more controlled growth than other lantanas so will work very well in combo pots and baskets.

Coleus FlameThrower series (Ball FloraPlant), The Gardens at Ball

We didn’t really have heat this year, especially in regards to our night temperatures. I would have to say, though, that we definitely stressed out some of the FlameThrower series and they came back really well. FlameThrower is a compact- to medium-sized coleus with great color and texture. Performs well in full-sun.

Coleus Under the Sea Copper Coral (Hort Couture), Mississippi State University

The multicolored foliage of Copper Coral held its color throughout spring and summer on dense, bushy plants, both in container and ground trials. Hot summer days did not stop this variety, as long as plants were regularly watered.

Gerbera Garvinea Sweet Smile (Florist), Young’s Plant Farm

The garden performance of the Garvinea series is amazing. They are Gerbera daisies that not only hold up well but even thrive in our Alabama summers. Sweet Smile is a new variety that has large, beautiful yellow flowers. The color is so bright!

Ipomoea batatas ‘FloraMia Cameo’ (Dümmen Orange), North Carolina State University

True to its nature, this sweet potato got bigger and better as the season went along. Each ‘FloraMia Cameo’ plant covers a lot of space with its attractive dark purple/black heart-shaped leaves. It gives a lot with minimal input.

Pepper Aji Rico (PanAmerican Seed), Raker Trial Gardens

This plant produced fruit all summer long. We had a very dry summer this season, and even though we in-line water, it held up well when other varieties stopped producing. We limited watering the last half of the season and it did not affect this variety at all.

Petunia ColorRush Pink (Ball FloraPlant), Iowa State University

This plant had tons of flowers and didn’t flag during our hottest weeks (and there were a lot of them this summer). ColorRush Blue does deserve an honorable mention for holding up as well as it did for as long as it did, but while pink still looks beautiful, blue has finally just about completely died out as of the end of September.

Phlox Gisele series (Selecta One), Mast Young Plants

This series was bred for easier propagation, heat tolerance and large flower clusters, and has been excellent in our trial gardens both in its first year in 2016 and again this year. These phlox will grow to about 12 inches tall and stay in flower all summer long.

Best heat-tolerant perennial

Eucalyptus Silver Drop (Proven Winners), Mast Young Plants

These silvery foliaged plants make beautiful thrillers in containers or background plantings in a garden bed, and can also be used in dried or fresh flower arrangements. The essential oils in eucalyptus smell great and have a wide range of medicinal uses. Silver Drop is a more cold-hardy variety, hardy to Zones 9-11 but reported to even have survived winters in Zone 7.

Gaillardia SpinTop Yellow Touch (Dümmen Orange), North Carolina State University

Nice compact plants that are covered with large, attractive orange flowers with the edges dipped in yellow. Thrived in our heat.

Pennisetum ‘Red Rocket’ (Intrinsic Perennial Gardens), Dallas Arboretum and Botanical Garden
Salvia Mirage Cherry Red (Darwin Perennials), The Gardens at Ball

This S. greggii had continuous color through all weather extremes. The bold, brightly colored blooms stood out in the landscape. The Mirage series is self-branching and resists breaking. It is very heat-tolerant and takes the cold as well – it will continue to bloom well into the fall and is hardy to Zone 7. Very low maintenance with high-color impact.

Sedum Rock ‘N Grow ‘Popstar’ (Proven Winners), Walters Gardens

Finding a low-profile sedum that doesn’t lodge (open up) can be a challenge, however, ‘Popstar’ rose to the occasion. For most of the year, ‘Popstar’ looks great as a foliage plant with blue-green leaves. Later in the season, it explodes with salmon pink flowers. With its great habit, ‘Popstar’ is definitely an improvement over S. cauticola, which can’t seem to bear the weight of its own flowers. We’ve definitely had dry, hot weather here in Michigan (including record-setting heat in September), but ‘Popstar’ didn’t even bat an eye.

Verbena Santos Purple (Kieft Seed), The Gardens at Ball

A tough, long-lasting landscape perennial through Zone 7. Very heat and drought tolerant, and performs well in cool weather, too. Santos Purple is compact and upright. The well-branched plants bloom late-spring through the summer. It showed high powdery mildew resistance. Makes a great addition to combo planters or baskets.

Best pollinator-friendly annual

Beedance Red Stripe Bidens (Suntory), Plantpeddler

All of the Beedance series are great bee attractors but the Red Stripes has the best color and flower power of them all. Full plant that flowers heavily throughout the season. The yellow flower with red stripe is very attractive to bees and gardeners alike.

Celosia ‘Asian Garden’ (Murakami Seed), Iowa State University
Celosia ‘Asian Garden’ (Murakami Seed), North Carolina State University

This pink/magenta colored spike-flower celosia must have been pumping out whatever pheromone the pollinators like — it was constantly being visited.

Pentas Graffitti Lipstick (Benary), Dallas Arboretum and Botanical Garden
Portulaca Wagonwheels series (Danziger), Raker Trial Gardens

All the portulaca typically do well with bees but the Wagonwheels, especially the Vanilla Cherry, were always covered with pollinators.

Salvia Grandstand Purple (Green Fuse Botanicals), Mast Young Plants

This salvia on steroids flowered all summer in our comparison garden and was also our pick for the best performer in the purple salvia category. The pollinators thought it was pretty great, too.

Salvia Mystic Spires Improved (Ball FloraPlant), The Gardens at Ball

Impressive color and stature in the landscape and attracted bees, butterflies and hummingbirds all season. The improved genetics means Mystic Spires holds its flower longer and has a brighter blue color in the garden. It’s a sturdy, dark green-leafed plant with a naturally compact habit that’s very free-flowering.

Salvia Rockin’ Deep Purple (Proven Winners), Young’s Plant Farm

This salvia is covered with deep blue flowers all summer long. In our garden, this salvia was constantly covered with bees, butterflies and hummingbirds. They all love this plant!

Salvia × hybrida Rockin’ Playin’ the Blues (Proven Winners), Mississippi State University

This salvia was in flower when planted in April and did not stop producing new flower stalks through the summer, even without pruning. Flowers were a favorite of pollinating insects.

Salvia × hybrida ‘Rockin’ Playin’ the Blues (Proven Winners), South Dakota State University

This was, by far, our most pollinator attractive plant. It performed best when grown in full sun in a ground bed, but was great no matter where it was grown. It earned a score of 3.8/5 but here were some comments: Plants are very well branched, uniform in height and floriferous. Flower spikes are quite tall and held well above the foliage. Foliage is dark green. Plants are uniform in height. They have dark green foliage with long terminal flower spikes on each stem. They are very attractive to pollinating insects, especially butterflies and hummingbirds.

Zinnia Profusion Red (Sakata Seed), Smith Gardens

Bright red flowers are a pollinator favorite and definitely make a statement in the border of a garden.

Best pollinator-friendly perennial
Dianthus Rockin’ Red (Kieft Seed), The Gardens at Ball

Very attractive color and a great landing pad for butterflies and bees. The soft scent and lacy florets were appealing in the garden all season. Reliably overwintered in Zone 5 and retained its dynamite RED color.

Echinacea Cheyenne Spirit (Kieft Seed), Mast Young Plants

This colorful assortment of coneflowers isn’t new, but still continues to wow us in our trial gardens every summer. Hardy to Zone 4 and first-year flowering too!

Monarda 'MO 017' (Dümmen Orange), North Carolina State University

Monardas are known for being pollinator-friendly and this one did not disappoint. ‘MO 017’ is a compact, well-behaved clumper that blooms prolifically. It is still in the experimental phase but one to keep a watch on.

Panicum Prairie Winds ‘Apache Rose’ (Proven Winners), Dallas Arboretum and Botanical Garden
Penstemon barbatus ‘Twizzle Purple’ (Van Hemert Seeds), Iowa State University

This plant is a first-year blooming perennial from seed. The color is an eye-catching purple that draws pollinators in with tube-shaped flowers. ‘Twizzle Purple’ overwinters well through bitter Iowa winters and blooms even earlier the second year.

Salvia ‘Bumbleberry’, Walters Gardens

If you’ve ever been around salvias in peak during the spring, you know that honeybees adore these flowers. ‘Bumbleberry’ has performed excellently in our finished plant trials, along with ‘Bumblesky’ and ‘Bumbleblue’. They’re easy to maintain as they are naturally compact, but vigorous enough to finish a container. We love the perfect fuchsia pink flowers on the dark purple calyxes.

Salvia Fashionista Midnight Model (Walters Gardens), Smith Gardens

Such a great plant. Large flowers attract all kinds of pollinators from bees to butterflies to hummingbirds.

Salvia ‘Rose Marvel’ (Darwin Perennials), The Gardens at Ball

The large flower size of this salvia attracted many pollinating bees. The color was vibrant. The rich, deep rose color stood out in the trial beds. The ultra-large flowers provided more color and impact in the garden. ‘Rose Marvel’ also has a long flowering window for extended enjoyment.

Best overall performance: annual

Begonia Megawatt series (PanAmerican Seed) and Salvia Rockin’ Deep Purple (Proven Winners), Raker Trial Gardens

Begonia Megawatt series from PanAmerican Seed: All the varieties in this series were quite consistent. They flowered all summer long.

Top visitor pick: Salvia Rockin’ Deep Purple from Proven Winners.

We planted this near our parking lot and it was one of the first things our visitors saw and then commented on. It was very showy all season and attracted a lot of pollinators. Our visitors typically comment that it’s hard to pick a favorite, but this one stood out.

Celosia ‘Asian Garden’ (Murakami Seed), Iowa State University

This celosia was awarded an AAS award in 2017 and it’s easy to see why. The color is amazing, it can tolerate heat and drought, and pollinators love it. The longer and hotter the season, the longer the flowers grow and the wilder and woolier they look. ‘Asian Garden’ is easy to germinate from seed, but does not reseed excessively in the garden.

Coleus FlameThrower series (Ball FloraPlant), Young’s Plant Farm

Chili Pepper, Salsa Verde and Spiced Curry are all from the FlameThrower series and were in the top 5 in our trial garden this summer. These coleus are compact and late to flower with interesting leaf shape and color combinations. Coleus is always a winner in hot Alabama summers!

Ipomoea SolarPower Black Improved (Ball FloraPlant), Mississippi State University

This ornamental sweet potato performs well in full sun, providing dark-colored foliage throughout the warm spring and hot summer, along with good ground coverage by the spreading vines.

Ipomoea SolarTower Black and SolarTower Lime (Ball FloraPlant), The Gardens at Ball

The first-ever self-climbing ipomoea. It makes a great vertical garden design element for trellises, arbors, obelisks, and tall mixed combos. Both Black and Lime did exceptional this year. SolarTower is an excellent foliage accent plant.

Lantana ‘Landmark Red’ (Dümmen Orange), Dallas Arboretum and Botanical Garden
Oh So Orange Hiemalis Begonia (Dümmen Orange), Plantpeddler

Overall No. 1 pick of the Plantpeddler Trials for 2016 and 2017. High vigor, controlled growth habit with sturdy stems and branching. Excellent performance in partial shade. Once in color, it stayed in color during cool and hot temperatures.

Petunia Crazytunia Frisky Purple (Westhoff), Smith Gardens

This variety looked beautiful in our garden this year and won first place at our June Garden Event. The bicolor flowers are striking and did not fade throughout the summer.

Petunia hybrid Supertunia Vista Bubblegum (Proven Winners), South Dakota State University

This year, once again, this was our best performing annual with an average rating of 4.8/5 over three evaluation periods, grown in a 14-inch container in full sun. Extremely well branched plants are densely covered with flowers, draping several inches over sides of container, nearly to the ground. Plants have foliage cascading down to the ground with excellent flowering nearly covering the foliage.

Salvia × hybrida Rockin’ Playin’ the Blues (Proven Winners), North Carolina State University

Uniform plants with complete plant flower coverage make this beautiful purple flower a must-have for all gardeners. Season-long flowering keeps pollinators in your garden.

Sunflower Sunfinity (Syngenta Flowers), Mast Young Plants

Sunflower Sunfinity is a breakthrough in sunflower breeding that produces many stems of bright yellow flowers all summer, as opposed to a traditional sunflower that has only one main flower and then is done. Sunfinity grows to about 4 feet tall and 3 feet wide, and can be used for cut flowers as well. Sunfinity are pollen free, so won’t leave a mess inside when used in bouquets, but still produce nectar that attracts beneficial insects.

Best overall performance: perennial

Coreopsis SunSwirl (Dümmen Orange), Smith Gardens

Great habit with large yellow pom pom flowers. The plants did not split like coreopsis have the tendency to do, and it was a definite showstopper in the gardens.

Dianthus Rockin’ Red (PanAmerican Seed), Mast Young Plants

Dianthus Rockin’ Red is a dynamite velvety red dianthus from PanAmerican Seed that is hardy to Zone 5 and very heat tolerant, flowering throughout the summer. It grows to about 2 feet tall and can be used in combos or as a back of the border garden plant.

Dianthus Rockin’ Red (Kieft Seed), The Gardens at Ball

Vivid red color on knee-high plants. Had a soft fragrance as well. This barbatus interspecific variety works great as a perennial border plant with durable performance and it reliably overwinters to Zone 5. The blooms are lacy on top of full and long-lasting plants.

Echinacea Kismet Raspberry (Terra Nova Nurseries), North Carolina State University

These compact coneflowers were covered in clear raspberry-colored flowers. They started blooming in June and there was still some sporadic flowering occurring in mid-September. The plants are very uniform in size.

Echinacea Sombrero Sangrita (Darwin Perennials), The Gardens at Ball
Excellent presentation – the burgundy flower stems really stood out.

The Sombrero series is well-known for its compact and floriferous habit, with rich, bright colors. It attracts birds and other pollinators, too. A great native choice for full-sun gardens.

Heuchera PRIMO ‘Black Pearl’ (Proven Winners), Walters Gardens

We were wowed right away by the visuals of this plant, and once we got it into production, we continued to be impressed. In our trials, when we found we could finish this plant from a plug to a gallon container in 6 weeks in summer, we were floored. It truly lives up to the PRIMO name of larger, vigorous plants. Additionally, its glossy black foliage makes it easy to get ‘Black Pearl’ to look showy in a container.

Portulaca ‘Colorblast Double Magenta’ (Westhoff), Dallas Arboretum and Botanical Garden
November 2017
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