Dr. Susan Hamilton, Director of the UT Gardens
James Newburn, Assistant Director
Jason Reeves, Curator of the Jackson UT Gardens
Beth Willis, Trials Coordinator
Betty Tipton, Plant Evaluation Coordinator
Note: Check local nursery availability of listed varieties at the UT Gardens website – http://utgardens.tennessee.edu.
The following report details the varieties of plants (annuals, perennials, tropicals, roses, trees and shrubs) which have performed best for the UT Knoxville and Jackson garden sites this past year.
Best in Show Annual
Calibrachoa Million Bells® ‘Trailing Magenta’ from Suntory was a low-growing variety that impressed everyone with its season-long show of numerous bright pink blooms resembling miniature petunias. Due to its height (3”) and trailing habit, this carpet-like annual was best sited in the front or edge of a planting bed or placed in a container.
Best Repeat Annual Variety
Begonia BIGTM ‘Rose with Bronze Leaf’ from Benary, produced masses of large, self-cleaning blooms above lush, glossy foliage. Tolerant of both shade and sun locations, this large, upright begonia was a standout in our gardens from early spring until frost. The BIGTM ‘Red with Green Leaf’ variety, also from Benary, performed equally well.
Best New Annual Variety
Pennisetum VertigoTM was a dramatic ornamental grass that featured broad blades of deep burgundy and reached a height of 3-5’. Because it produced no bloom, it was best used as a contrast to flowering plants in the landscape. From Proven Winners.
Top Annual Performers
Angelonia SerenaTM series (Lavender, Purple, and White) were seed-grown mounding annuals from PanAmerican. Each performed well all season, with perfect foliage and full blooms. Angelonia AngelmistTM ‘Spreading Purple Improved’ was an upright vegetative variety from BallFlora that featured lush growth and blooms all summer long.
Anisodontea Slightly StrawberryTM from Proven Winners was an unusual annual perfectly suited as a filler plant in the middle of landscape beds. Low maintenance, it featured soft pink hibiscus-type blooms.
Begonia Brandy® Improved and Nightlife Blush (from Benary) along with VolumiaTM Rose Bicolor (from Syngenta) were seed grown begonias that boasted heavy blooms all season. Like most begonias, these were well suited to part-shade or shady garden areas.
Bracteantha DreamtimeTM ‘Jumbo Light Pink’– The huge blooms on this mounding annual were unusual because they opened up each day and featured a beautiful range of soft pink colors. Ball FloraPlant provided this variety as well as the equally striking DreamtimeTM ‘Jumbo Pure White’ and DreamtimeTM ‘Jumbo Red Ember’.
Calibrachoa ‘Liberty Blue Vein’ and ‘Liberty Magenta’ from J.P. Bartlett were carefree annuals with dense, healthy foliage and numerous blooms. Million Bells® Brilliant Pink was a mounding variety from Suntory that performed very well. Proven Winners provided three notable varieties in the Superbells® series: Blackberry Punch – an unusual and striking color combination and the more typical Lavender and Yellow varieties.
Carex ‘Amazon Mist’ and ‘Prairie Fire’ were short ornamental grasses from Kieft that provided a nice contrast of color and texture to flowering plants.
Celosia ‘Fresh Look Gold’ (an AAS winner) and ‘Glorious Red’ (from Benary) featured healthy foliage and striking blooms all season long.
Cleome Senorita Rosalita® was a wonderful variety of an old-fashioned annual. This tall upright plant with spidery lavender blooms was well suited for the mid to back of a landscape bed but, as always, was short-lived and gone from the garden by the beginning of August.
Coleus (Solenostemon) ‘Rebel Rouser’ from Proven Winners. Grown for its foliage rather than its bloom, coleus always provides an excellent contrast to flowering plants in the landscape. This shade-tolerant variety had an attractive bold texture and color. Two other varieties from Proven Winners, Colorblaze® Alligator TearsTM and LancelotTM Cherry CordialTM were also great performers that tolerated shady garden conditions.
Diascia DiamonteTM Coral Rose was a surprise this summer. An annual that usually performs much better in cool season conditions, this AAS Winner variety held up well in the heat and humidity.
Euphorbia Diamond Frost® was, as usual, a carefree mounding annual. Profusely covered with tiny white blooms, it was a great filler plant that served as a contrast to annuals with larger more prominent blooms. From Proven Winners.
Gomphrena ‘Audray Purple Red’ from American Takii was a new spin on an old-fashioned plant. This full, mounding variety was absolutely loaded with bright, clover-like blooms all summer long and was well suited to the middle of a planting bed. ‘Audray Bicolor Rose’ was equally attractive, with a more sedate bloom color.
Hibiscus LuauTM ‘Peach Mai Tai’ was a dramatic annual with exceptionally large, striking blooms against dark green glossy foliage on a compact plant. LuauTM ‘Pink Paki’ was equally impressive. Both from Proven Winners.
Impatiens ‘Patchwork’ series (Peach Prism and Pink Shades), vegetative varieties from Ball FloraPlant, were non-stop bloomers all season long. The Super ElfinTM series (Cherry Splash, Red Starburst, Rose Starburst, and Violet Starburst), a seed-grown series from PanAmerican, provided a welcome splash of color in our woodland garden where the full, mounding annuals appreciated the shade.
Laurentia (Isotoma) ‘Avant-Garde Blue’ and ‘Avant-Garde Pink’, both from Thompson & Morgan had a full mounding habit, lacy foliage and delicate blooms that made them great fillers against plants with bolder texture or blooms.
Lobularia Snow PrincessTM was a ground-hugging annual that tolerated part-shade and was covered all summer long with dense panicles of small white blooms. From Proven Winners.
Lysimachia SuperstitionTM from Proven Winners was a carefree and vigorous groundcover annual with dark ruby-bronze foliage and bright contrasting yellow blooms.
Marigold (Tagetes) ‘Moonsong Deep Orange’ is an award-winning variety of the popular annual. Remarkably long-lasting in the landscape, it was disease-free all season long and remained liberally covered with large, bright blooms against attractive, lacy foliage. From AAS Winners.
Melampodium ‘Casino Light Yellow’ from American Takii was a mounding annual with striking, dense foliage and profuse, cheerful yellow blooms all summer long.
Nierembergia AugustaTM Blue Skies from Proven Winners was a deceptively tough performer, with delicate-seeming foliage and light-blue cup-like blooms that provided a season-long show.
Ornamental Pepper (Capsicum) ‘Black Pearl’. This AAS Winner has never failed to grab visitors’ attention in the garden. Its dark purple foliage was a wonderful contrast to the shiny black marble-sized fruits that ripened to bright red.
Osteospermum AstiTM White was an AAS Winner that was covered profusely with unusual blooms resembling a blue-eyed daisy. A mounding carefree annual that performed beautifully all summer long.
Petunia ‘Black Velvet’ from Ball FloraPlant was a vigorous trailing annual that boasted the blackest blooms ever and was quite eye-catching in the landscape. This solid black variety was joined by Ball Flora’s ‘Pinstripe’ and ‘Phantom’ varieties which featured black and cream blooms. The Supertunia® series (Vista Bubblegum, Vista Silverberry, Indigo Charm, and Lavender Skies) As always, this incredibly vigorous series from Proven Winners was covered in masses of clear pink blooms from early summer to frost. The AAS Winner varieties ‘Burgundy Trailing Type’ and ‘Opera Supreme Pink Morn’ were also vigorous and heavy blooming.
Salvia ‘Coral Nymph’ and ‘Lady in Red’ (from American Takii), ‘Forest Fire’ (from Benary), and ‘Red’ (an AAS Winner) were carefree and extremely vigorous varieties of Texas Sage featuring nonstop blooms all summer long. ‘Evolution’ (also an AAS Winner) and ‘Fairy Queen’ (from Benary) were great varieties of Mealycup Sage.
Sweet Potato Vine (Ipomoea) IllusionTM series (Emerald Lace and Midnight Lace) and Sweet CarolineTM series (Bewitched Purple, Bronze, Green Yellow, Light Green, Purple, Red, Sweetheart Light Green, Sweetheart Purple, and Sweetheart Red), all from Proven Winners, provided a riotous selection of colors and foliage textures. All were extremely vigorous vines that performed well all summer long.
Torenia Summer WaveTM series (Large Blue and Large Violet) from Suntory were mounding annuals covered with vibrant blooms that had an unusual ‘wishbone’ structure formed by joined anthers. These varieties performed best in a part-shade location.
Verbena Superbena® Royale Chambray was a Proven Winner selection that was simply perfect throughout the summer, with a ground-hugging habit and an unusual purple-blue bloom color.
Vinca (Catharanthus) TitanTM series (‘Apricot’, ‘Icy Pink’, and ‘Dark Red’), ‘Cherry Halo’, ‘Rose Halo’, and ‘Pacifica Orange’, all from PanAmerican Seed, along with ‘Pacifica Burgundy Halo’, an AAS Winner, boasted numerous blooms in attractive colors. All were maintenance free annuals with mounding habits that performed well all season long.
Zinnia ZaharaTM series (Double Cherry, Double Fire, and Starlight Rose) and Zowie! Yellow Flame (all AAS Winners) featured exceptionally gorgeous and heavy blooms throughout the season.
Achillea ‘Summer Berries’, although trialed as an annual, was actually a seed-grown perennial from American Takii that bloomed its first year in the garden, yielding extra value for your landscape dollar.
Amsonia hubrichtii – Arkansas blue star, thread leaf blue star. This fabulous plant has been chosen as the 2011 Perennial Plant of the Year™. From late spring to early summer, it features two- to three-inch wide clusters of small, light blue, star-shaped flowers with bright green fern-like foliage that turns a bright yellow-golden color in fall.
Coreopsis ‘Ruby Frost’ – Ruby frost tickseed. This 2010 hybrid coreopsis, from Terra Nova Nurseries, has a ruby colored bloom fringed with a frost-white margin. This perennial is ideal as an accent or in mass plantings for the mixed bed, border, or containers. ‘Cherry’, ‘Citrine’, and ‘Pineapple Pie’, also from Terra Nova, were also beautiful selections.
Echinacea ‘Paradiso Mix’ (from Sahin) and Prairie SplendorTM (from Syngenta) performed well in a hot and humid summer that was hard on other trialed coneflowers. Both had profuse blooms and held up well throughout the season.
Gaillardia x grandiflora ‘Arizona Apricot’ – Arizona apricot blanket flower is a 2011 All-America Selections winner and a wonderful perennial for our region. This new variety offers an apricot color not seen in Gaillardia before. ‘Arizona Red Shades’ (from Benary) along with AAS Winners ‘Apricot Shades’ and ‘Mesa Yellow’ were strong varieties. All offered bright and cheerful bloom colors with healthy foliage and profuse blooms throughout the summer.
Gaura ‘Summer Breeze’ (from Jelitto) and ‘The Bride’ (from Kieft) were stunning, airy annuals which worked well in the middle to back of garden beds. The wands were liberally covered with small white blooms until frost.
Lavender (Lavendula) ‘Ellegance Snow’ and ‘Ellegance Purple’ from Kieft brought a welcome herbal fragrance to the garden, with heavy blooms and healthy foliage throughout the season.
Miscanthus sinensis ‘Gold Bar’ – Gold bar dwarf zebra grass. This slow-growing grass can take up to five years to reach a height of five feet. It is upright and compact with a spiky texture. All these attributes make it ideal for smaller gardens where other ornamental grasses can quickly take over.
Paeonia x (Intersectional hybrid)– Itoh peony. Itoh hybrids have the best characteristics of both herbaceous and tree peonies. They are vigorous, easy to grow, and very long-lived. They are relatively low plants, rarely growing taller than 45 inches, but they feature the large blooms of tree peonies held up on sturdy stems.
Phlox hybrids – Summer phlox. Good breeding has brought an array of fantastic new phlox hybrids that display wonderful characteristics. Some of the hybrid phlox that are great performers for our Tennessee landscapes are the Cocktail Series: ‘Watermelon Punch’, ‘Pina Colada’, ‘Cosmopolitan’, ‘Peppermint Twist’, ‘Purple Kiss’, and ‘Tequila Sunrise’ as well as the Flame Series: ‘Pink’, ‘Lilac’, and ‘Purple’.
Physostegia ‘Crystal Peak White’ from Benary, was trialed as an annual, but was actually a perennial that bloomed the first year from seed. It provided dense, profuse blooms in mid-summer and persisted in the landscape even after frost.
Sedum ‘Crystal Pink’ from Terra Nova was a delightful succulent selection with frothy yet dense pink blooms. Its water-wise nature made it well suited to rock gardens or well-drained landscape beds.
Stipa ‘Pony Tails’ from Kieft. This under-used ornamental grass provided a wonderful fine texture, graceful weeping form, and sense of movement to the landscape. As with other grasses, it was best used as a contrast to flowering plants.
Verbascum hybrids – Ornamental mullein. An upright vertical perennial with tall flower spikes rising from a basal rosette of woolly gray-green leaves. Available in colors ranging from pure white to pinks, peaches, yellows and lavenders. Some great selections to use are ‘Southern Charm’, ‘Caribbean Crush’, ‘Jackie in Pink’, ‘Jackie in Yellow’, ‘Sixteen Candles’ and ‘Wedding Candles’.
Aechmea ‘Wally Berg’ – Wally Berg bromeliad. A beautiful red-orange selection developed by the late Wally Berg of Sarasota, Florida. A new, unusual and striking color.
Ananas comosum – Pink variegated pineapple. Everyone loves the creamy white, pink, and green variegated foliage of this pineapple plant. It stands out as a striking specimen plant.
Kalanchoe thyrsiflora ‘Flapjack’ – Flapjack kalanchoe. This clumping succulent has large flat blue-green leaves with red leaf margins and — you guessed it — is shaped like a flapjack. When grown in full sun the leaf margins become even redder and broader. This is truly a desert plant, which makes it an ideal plant for a xeriscape or low-water usage area.
Musa acuminata ‘Siam Ruby ‘– Siam Ruby Banana. Rare red-leaved banana from the wilds of New Guinea. Originally sold for as much as $1500! Very fast growing, grows to 8 feet tall. Not believed to be cold hardy.
Musa velutina – Pink velvet banana. Beautiful pink flowers and fruit make this a striking banana. Rarely exceeding 6′ tall, this banana produces copious flower stalks near the top of the trunk, starting in late summer. Each stalk produces clusters of small, pink, velvet bananas that peel themselves when ripe. Not good for eating.
Trees and Shrubs
Acer palmatum var. dissectum ‘Red Select’ – Red select cutleaf Japanese maple. One of the best maples known for retaining red foliage all season. Its red lacy foliage turns a brilliant crimson fall color. It has a slightly weeping form and will ultimately top out at about 12-15 feet tall with a generous spread up to 10 feet wide.
Callicarpa americana ‘Welch’s Pink’ – Welch’s pink American beauty berry. This new introduction is named for its pink midsummer flowers and pink autumn berries. It grows 3-6 feet tall and thrives in full-sun and partial-shade.
Camellia sinensis – Tea camellia or tea bush. This dense evergreen shrub grows to between 4 feet and 6 feet tall and just as wide. It produces leathery, dark green leaves and covers itself each fall with fragrant white flowers. ‘Rosea’ is one with pink flowers. ‘Shirotae’ is a selection with pewter-colored leaves with white margins, and ‘Silver Dust’ has new growth that emerges almost white. ‘Gold Splash’ has large green and yellow variegated leaves.
Cotinus coggygria ‘Grace’- Purple smoketree or smokebush. This hybrid is a lovely deep mauve that flashes reddish leaf undersides. It has large misty blooms, the feature that gives the plant its common name. Can be left to grow as a small tree up to 15 feet tall or managed as a shrub if pruned back severely each year.
Gardenia jasminoides ‘Kleim’s Hardy’ – Daisy gardenia. Produces masses of fragrant, single, daisy-shaped, white flowers in late spring/early summer. Mounding habit with very dark green, lustrous foliage and heavier blooms than other gardenias. Grows up to 3 feet.
Ginkgo biloba ‘Mariken’ – Mariken maiden tree. A wonderful dwarf cultivar. This slow growing selection is ideal as a container or specimen plant. It grows only 2-3 feet tall and can develop a pendulous, weeping shape when mature. It has brilliant golden foliage in fall.
Juniperus chinensis ‘Holbert’ – Holbert Chinese juniper. Spreading growth habit of 8-9 feet wide and just 2-3 feet high. Great blue foliage holds color through the winter months.
Nyssa sylvatica ‘Zydeco Twist’ – Zydeco twist black gum. This contorted-branched black tupelo (or sourgum) has an especially striking form after the vivid red fall foliage drops. Tolerant of a wet site, it grows to 20 feet tall.
Thuja occidentalis ‘Sunkist’ – Sunkist oriental arborvitae. One of the brightest yellow-gold conifers available. Tolerant of partial shade to full sun and a moist to dry and well-drained site. Grows up to 4 feet tall and 2-3 feet wide.
Thuja orientalis ‘Franky Boy’ – Franky boy oriental arborvitae. Finely textured foliage and bright chartreuse color that turns bronzy-orange in the winter make this a winning year-round plant. Growth habit creates a wonderful, dwarf conifer with an overall plant form of a tear drop.
Thuja orientalis ‘Van Hoey Smith’ – Van Hoey Smith oriental arborvitae. Grows up to 6 feet tall. Beautiful variegated green and gold finely textured foliage.
Viburnum setigenum – Tea viburnum. A great native shrub with showy spring blooms, good fall color, and outstanding fall fruit. Many mistake this for a winterberry holly because it is also deciduous. Grows 8’-12’ tall and 5’-8’ wide. Wonderful shrub for attracting birds.
Rosa ‘Carefree Marvel’ – Carefree marvel shrub rose. This bright, deep pink rose is a low growing rose with a broad habit. Grows up to 2 feet tall and 3-4 feet wide. Disease resistant and low maintenance, it is ideal for spilling over a rock wall or ledge.
Rosa ‘Kimberlina’ – Kimberlina floribunda rose. This 2009 Floribunda of the Year® winner is outstanding. The soft pink blooms would work with any color combination especially with its dark green foliage. Touted as being one of the most vigorous floribundas ever introduced.
Rosa ‘Lynn Anderson’ – Lynn Anderson hybrid tea rose. A beautiful, vigorous hybrid tea with a mild fragrance. Its creamy, white center blends to light then dark pink edges.
Rosa ‘Rainbow Sunblaze’ – Rainbow sunblaze miniature rose. This rose has beautiful double flowers that stay well above the foliage. The center of the bloom is yellow with the outside petals a contrasting orange-red.
Rosa ‘Tournament of Roses’ – Tournament of roses hybrid tea rose. A soft, delicate pink colored rose that is very fragrant. This is a selection that looks great from a tight bud until fully open.