The Best New Trees and Shrubs of 2021

February 2nd, 2021

   A miniature version of the popular Knock Out rose, a super-short clematis that can be used as a groundcover, and three new dark-leafed shrubs are among the best new trees and shrubs debuting in the 2021 growing season.

   Growers, local garden centers, and other plant experts picked the following for my annual January four-part, best-new-plants series.

   Today’s best new trees and shrubs of 2021 is the final installment of this year’s series.

   Part one on best new vegetables and fruits of 2021 appeared on Jan. 12, part two on best new annual flowers of 2021 appeared on Jan. 19, and part three on best new perennial flowers of 2021 posted last Tuesday, Jan. 26.

   Some of the following new tree and shrub varieties are available online and in some plant catalogs. Most also will be available in local garden centers beginning in April.

   The details:

Petite Knock Out roses

   The long-blooming, disease-resistant Knock Out family of roses has been one of the top-selling landscape plants for years.

   New for 2021 is what Star Roses and Plants social media manager Leah Palmer calls a “game-changer” – the first miniature Knock Out.

   The new Petite Knock Out “has all the same great qualities as the other Knock Out roses, just in a perfectly petite size,” Palmer says.

   This variety grows only 18 inches tall and blooms almost all season long in a non-fading red color. Most standard Knock Outs grow four feet tall and wide – or more.

   “Petite Knock Out also comes in tree form,” Palmer adds. “Other tree roses bloom less frequently, but this one blooms throughout the season. It’s also smaller than other tree roses, making it more versatile and usable in a range of settings.”

Clematis Little Lemons

   Knock Out roses aren’t the only shrunken-down new woody plants.

   Breeders at Concept Plants have come up with a new super-compact clematis vine that’s more at home in a pot, hanging basket, or serving as a groundcover than growing up a trellis.

   Maria Zampini, president of the Ohio-based UpShoot plant introduction company, picks Little Lemons as her favorite new woody plant of 2021 for its compact size and bright yellow, hanging, bell-shaped flowers.

   Zampini says the plant also blooms for a long time, starting in May and running into September.

   It grows only about a foot tall and spreads about two feet, ideally in full sun to part shade.

Sweetshrub ‘Burgundy Spice’

   This shrub variety from New Jersey’s Pleasant Run Nursery gives a radical new look to an old-fashioned native plant.

   Sweetshrub ‘Burgundy Spice’ has the familiar fruity-fragrant, late-spring maroon flowers but sports dark burgundy-purple foliage, earning it the best-new-shrub pick of Brandon Kuykendall, the nursery manager at Ashcombe Farm and Greenhouses in Monroe Twp.

   “I was skeptical about it holding the color all summer, but the few I had last year kept their burgundy leaf color through summer,” he says. “It gets eight feet tall and wide and does well in full sun to part shade.”

   Deer don’t like sweetshrubs, and ‘Burgundy Spice’ closes the season by turning leaf shades of yellow and amber in fall.

Ninebark Sweet Cherry Tea

   Here’s a second dark-leafed native shrub that both reblooms and is one of the most compact varieties of ninebark yet.

   Sweet Cherry Tea is a ninebark that Plants Nouveau co-owner Angela Treadwell-Palmer calls “truly compact, barely reaching three feet tall and wide…” and without frequent pruning, too.

   “It also has a bushy habit with no long, arching branches, so it fits easily into any border or foundation planting,” Treadwell-Palmer adds. “The foliage begins wine-red and ages to a deep maroon and stays that color until fall. It’s covered in flowers in early summer and then has sporadic flowers again in late summer and fall, making it the first ninebark to rebloom.”

   The flowers open to soft pink, and birds like Sweet Cherry Tea’s tiny, non-messy fruits.

   Like other ninebarks, Sweet Cherry Tea is very cold-hardy, drought-tolerant once established, and best grown in full sun. Deer sometimes target ninebarks, though.

Elderberry Laced Up

   A third new version of a dark-leafed shrub is this unusually narrow form of elderberry.

   Robert Kadas, owner of Highland Gardens in Lower Allen Twp., picks Laced Up as his favorite new 2021 woody plant.

   “It’s super-hardy and able to withstand the toughest conditions, even poor soils,” Kadas says. “What makes this unique variety so cool is the deep black foliage, but it also grows on straight-up stems.”

   Like the popular but bigger Black Lace variety, Laced Up’s foliage is also lacy and feathery. It flowers pink in early summer and will get some berry-like black fall fruits if pollinated by Black Lace or Black Beauty.

   Laced Up grows six to eight feet tall but only three to four feet wide in either full sun or part shade.

Hydrangea Limelight Prime

   The summer-blooming Limelight hydrangea is a popular shrub favorite that’s getting a facelift from Proven Winners this year.

   The new Limelight Prime is a “more refined version” of Limelight and is “earlier to bloom and holds its lime flower color longer,” says Proven Winners public-relations specialist Natalie Carmolli. “It then transitions to a bright, bold, bubble-gum pink and finally to rich punch pink.”

   Limelight Prime also has darker green leaves and is more compact, upright, and sturdy than the original Limelight, which Carmolli says is remaining on the market.

   Limelight Prime grows about four to six feet tall and four to five feet wide, while Limelight usually grows one to two feet taller and wider.

   Like Limelight, Limelight Prime is a long and heavy bloomer with big, cone-shaped flowers.  Both do well in full sun to part shade.

Kousa dogwood ‘Heart Throb’

   This small tree variety joins recently introduced Scarlet Fire to make a duo of impressive new pink-blooming kousa dogwoods, which are more bug-, disease-, and clay-soil resistant than our American dogwoods.

   Erica Shaffer, garden designer for Black Landscape Center and former manager at Highland Gardens, picks ‘Heart Throb’ as her favorite new tree of 2021.

   “It’s a bit smaller-growing than other kousa dogwoods with huge, four-inch deep-pink flowers covering the tree for four to six weeks, beginning in June,” she says. “Unlike our native dogwoods, it does great in full sun. Autumn color is deep red and purple. With age, the bark begins to texture, adding lovely winter interest to go along with red fruits that resemble cherries.”

   Figure on a size of 20-by-20 feet in full sun to part shade.

Mock orange Illuminati Arch

   Chris Wallen, a grower at the wholesale Quality Greenhouses near Dillsburg, picks this new Proven Winners flowering shrub as his top woody plant of 2021.

   Mock oranges were a staple of older landscapes for their amazingly sweet fragrance, but they fell out of favor because of their tendency to become overgrown and to stop flowering with age.

   “Gone are the times of tattered, overgrown mock oranges,” Wallen says of Illuminati Arch.

   He says this newcomer features a “profuse bloom of white, citrus-scented flowers in early summer and rugged, deep-green foliage on an improved four-by-four-foot habit of graceful, arching branches.”

   The flowers are white, and like other mock oranges, Illuminati Arch is a species that’s seldom bothered by deer. Give it full sun to light shade.

Golden dawn redwood ‘Soul Fire’

   Another newcomer that Treadwell-Palmer picks as a 2021 standout is this new golden-foliage version of the stately dawn redwood tree.

   “This is one of the few needled trees to get amazing fall color and lose their needles,” Treadwell-Palmer says.

   ‘Soul Fire’ is typically impressive in fall, turning a coppery-orange shade. The bonus is that instead of having soft, flat, green needles all season, ‘Soul Fire’ gets two-toned rosy-orange needles in spring, followed by bright chartreuse needles until the fall turn.

   The color is much improved, Treadwell-Palmer says, over the only other yellow-needled dawn redwood variety, called Ogon.

   “’Soul Fire’ is much more yellow and does not fade or burn in full sun,” Treadwell-Palmer says. “In my garden, it’s truly a beacon in the corner. Your eyes are drawn to the color of the foliage.”

   Standard dawn redwoods can get very big in time – reaching 80 to 100 feet. ‘Soul Fire’ is a slower, more dense grower that Plants Nouveau labels as being about 18 feet tall and 15 feet wide in 20 to 25 years.

   As with all dawn redwoods, this one can take wet or dry soils and full-sun to part-shade locations. Deer don’t find them tasty.

Sand cherry First Editions Jade Parade

   Most gardeners know sand cherries as those rangy, old-fashioned, wine-colored shrubs that tend to be short-lived due to a range of bug and disease threats (especially black knot).

   Minnesota-based Bailey Nurseries, one of the nation’s largest woody-plant growers, is touting a tougher newcomer that also grows more as a woody groundcover than upright shrub.

   Bailey spokesman Ryan McEnaney says the new Jade Parade sand cherry has branches that “arch upwards and spread rather than just creeping along the ground.”

   The leaves are bluish-green, turning red-orange in fall. The plants flower white in spring and then produce small black cherries in late summer.

   “When I was in the garden with (Jade Parade) this spring, you could hear the hum as you approach, there were so many pollinators covering it,” McEnaney said.

   Figure on a height of two to four feet and a spread of six to eight feet. Sand cherries grow best in full sun but are sometimes browsed by deer.

Dwarf lilac New Age

   Both Star Roses’ Palmer and Katie Dubow of Chester County’s Garden Media Group like the first two entries in this new dwarf lilac series.

   Dubow points to New Age’s mildew-resisting ability as well as the plants’ compact habit and heavy bloom of fragrant flowers in May.

   Palmer says the habit is also dense and tends to fill out the whole way to the base of the plants, solving the issue of “bare legs” that many gardeners don’t like in many lilac varieties.

   New Age is debuting in two colors this spring: New Age White and New Age Lavender.

   The plants flower best in full sun and grow to five to six feet tall and four to five feet wide in five years. They’re an occasional but not common target of deer.

Osmanthus (false holly) ‘Party Lights’

   Black Landscape’s Shaffer likes this multi-toned broad-leaf evergreen, which looks much like a holly, as her favorite shrub of 2021.

   “This new variety is making me swoon with a spring display of strongly colored pink, cream, and  yellow foliage,” Shaffer says. “It’s so pretty! And it’s a compact plant, too, growing only to about five feet tall and wide.”

   ‘Party Lights’ is also deer-resistant and grows well in full sun to mostly shaded locations.

   It’s cold-hardy in our usual winters but can suffer winter leaf damage in a very cold, windy winter. A wind-protected eastern foundation bed is ideal.