2020 Top Ten Performing Annuals
Steve Poppe, Horticulture Scientist
Esther Jordan, Communications Specialist
The 2020 growing season has truly been like no other in the Horticulture Display Garden at the University of Minnesota West Central Research and Outreach Center (WCROC), Morris, MN. Amidst the swirl of uncertainties and unknowns that a global pandemic brings, the Horticulture Display Garden became a place of solitude, a slice of normal, and offered respite and hope to those that visit.
Nearly 450 annual flower varieties were trialed during the 2020 growing season at the U of MN WCROC. The newest cultivars of annual flowers representing 18 plant breeding companies from around the world were planted over 4 acres of spectacular public display gardens. Forty percent of the annual flowers were grown from seed, while the remaining came as vegetative cuttings.
Due to the favorable spring conditions, we started planting annual flowers in garden beds on May 21, which is about a week earlier than normal. Sufficient precipitation paired with abundant sunshine and warmth brought about a beautiful display that was enjoyed by many. Annual flowers peaked in late July into early August.
As part of the annual flower process, plants are evaluated up to five times during the growing season in order to assess each variety’s performance. We use a 1 to 5 scale for providing a horticultural rating (1=poor, 2=below average, 3=average, 4=above average, 5=excellent). Plants are rated on performance, color, vigor, uniformity of habit and flowering, flowering numbers relative to others, insect and disease resistance, and uniqueness. The data is taken by the same individual every time to reduce variability in scoring. Evaluations began 3 weeks following planting. Only the highest rating cultivars earn the distinction of a Top Ten Performing Annual recommendations for Minnesota. See a complete list of all trial results.
Even though the annual flowers are under evaluation, the plants are placed into an aesthetically pleasing design, allowing visitors to enjoy the beauty of the Garden. The Horticulture Display Garden has been an All-America Selections (AAS) Display Garden since 1990. The AAS award recognizes a flower or vegetable variety proven to have superior performance throughout the North American continent. An AAS Display Garden provides the public an opportunity to view the new AAS winners in an attractive well-maintained setting. Additionally, the Horticulture Display Garden is the only AAS Trial Ground site in Minnesota, where AAS entries are planted next to comparisons and evaluated by an AAS Trial Judge.
Virtual tours of the Horticulture Display Garden are available for those unable to visit in person.
2020 Top Ten Performing Annuals
Angelonia Aria Blue performed exceptionally well in both a container and in our garden landscape. Excellent uniform habit with good overall growth. Slightly larger plant, good flower stem strength and more flowers than the other 12 Angelonia cultivars we trialed in 2020.
Begonia Dreams® Garden Macarouge flowered relentlessly all summer long with numerous eye-catching single, scarlet-red blooms with a yellow center plus clean dark green foliage. Excellent performance in our shady garden with minimal maintenance. Does best if grown in a container.
Bracteantha Granvia® Gold is a strawflower that had large bright yellow flowers and a center that turns orange as the flower ages. Trialed in a large block planter and exposed to very warm temperatures. These vigorous growing plants were resistant to mildew, a common disease found in earlier strawflower cultivars. Can be grown as a cut flower for fresh or dried displays.
Gomphrena Truffula® Pink the most outstanding feature of this cultivar was how early it flowered as compared to other gomphrena varieties we have trialed in the past. Had a well-balanced habit that showed off numerous hot-pink flowers that covered the plant. Truffula® Pink is a tough and durable plant that is easy to care for and requires no deadheading. Attracts many bees and butterflies. Can be used for cut and dried flowers.
Marigold erecta Big Top™ Yellow is a very easy to grow marigold that has abundant fully double yellow blooms all summer long. Big Top™ Yellow is a vigorous cultivar with no disease issues and is well-suited to challenging weather conditions. Occasional deadheading the old flowers will keep new buds coming, and you'll get even more color. This marigold is perfect for the gardener looking for an easy-to-grow annual from seed.
Petunia Amore™ Queen of Hearts is a unique bicolor petunia with red and yellow striped petals that displays five red hearts on each 2 1/2” blossom. Queen of Hearts has a semi-trailing habit that grew exceptionally well and was smothered in eye-catching flowers in our 2020 garden bed.
Petunia SuperCal® Rose is a unique blend of petunia and calibrachoa that maintained bright vibrant flowers with no fading. This petunia had exceptional performance in both a hanging basket and in the display garden beds. Performed well all season, had numerous blooms, and bounced right back after a rain. No deadheading needed.
Scaevola Surdiva Blue Violet withstood our summer heat and provided continuous color throughout the season. The semi-trailing habit is easy to grow and maintain in a hanging basket. Besides the outstanding blue violet flower color, the foliage remained bright green throughout the entire summer.
Vinca Valiant™ Orchid had superior garden performance in 2020. Its most outstanding feature was the uniformity of all the plants in our garden bed. The showy lavender star-shaped flower blossoms with a white eye created a striking look in our full sun garden location. Its glossy leaves remain dark green in color all season long. Vincas will do well if you can provide plenty of sun, heat and drier conditions.
Zinnia Double Zahara™ Yellow Improved features fully double, large bright yellow flowers with a very compact bushy plant. The flowers sit atop the clean green foliage and made a bold statement in our garden beds in 2020. For optimum performance, plant zinnias in a well–drained garden soil and occasional deadhead to improve appearance.
All flowers in the Horticulture Display Garden are labeled, allowing visitors to take note of top performing cultivars under regional conditions. The Horticulture Display Garden is open daily from dawn until dusk; admission is free. The Garden is located at 46352 State Hwy 329, Morris, MN. Location and directions to the Horticulture Display Garden.
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