University of Vermont Extension
Department of Plant and Soil Science
CHOICE PERENNIALS FOR 2011
Dr. Leonard Perry, Extension
University of Vermont
Each year, members of the
Perennial Plant Association-- the industry group representing
professional garden designers nationwide—vote on their top
perennials. From the final group of new cultivars
(cultivated varieties), or those deserving wider use, the perennial
the year is chosen. The elite group of
perennials voted by professionals is a good place to start when
from the thousands available for your own garden. This year the
list includes a couple for
sunny sites, and a couple for shady sites.
There were two perennials named
last year, and voted again this year, to the top list. 'Northwind'
is an ornamental switchgrass (Panicum
virgatum) with bluish-green foliage, compared to the green of
or reddish of some cultivars. It is also
one of the most upright of the switchgrasses, many tending to flop
age later in the season. The 4 to 5-foot
clumps are topped, late in the season, with one to 2-foot flowery
"panicles" of small yellowish flowers.
As with all switchgrasses, it
prefers full sun and a moist and fertile soil.
It will tolerate sandy or clay soils, and drought once established.
It is hardy to much of the north (USDA zone 4
or -20 to -30 degrees F average low in winter). This perennial looks
masses, in the middle to back of borders, on slopes, and combined
Another repeat from last year is 'Caramel',
one of the many new coralbells (Heuchera), grown mainly for
leaves in light and dark shades. It does
flower in warm areas with light
pink small flowers on spikes above the foliage in early summer.
This is one of the selections
of the hairy coralbells (H. villosa), a southeastern U.S.
although it originated as a chance seedling in France. Under good
conditions and warm climates it
can reach 15 inches high and a bit wider.
'Caramel' is listed as hardy to
USDA zone 4, with trials underway at the University of Vermont on
of this and other coralbells. It does
best in full sun in the north if kept watered, part shade in the
south. The best soil for it is a rich, moist loam
but well-drained. Try 'Caramel' in masses
in borders, under shrubs such as roses, along edges of beds and
paths, and in
containers. Contrast the leaf color with
that of darker blackish coralbells, or contrast the leaf texture
‘Hot Lips’ is a cultivar of our
native turtlehead (Chelone lyonii), a
long-blooming perennial with rosy-pink flowers that resemble a
(with its mouth open). Flowers in mid to
late summer are on reddish stems, between 2 to 3 feet high, in
the tips. Both the stem color and the
dark green leaves make this cultivar different from the species. It
is attractive paired with golden-leaved
sedges (Carex), astilbe, or
This plant is hardy to at least
USDA zone 4, and prefers full sun (over 6 hours a day) to part shade
(4 to 6
hours of direct sun). Unlike many
perennials it thrives in moist soils, but tolerates average ones, so
would be a
good candidate for a rain garden. It
also tolerates somewhat alkaline soils better than many perennials.
Turtlehead is a long-lived and low
maintenance perennial. It can be
propagated by division in spring, or rooting stem cuttings in water
‘Jack Frost’ Siberian bugloss (Brunnera macrophylla) also may
heart-leaf brunnera from the shape of its leaves, up to 6 inches
wide. This spring-bloomer has small blue flowers
resembling forget-me-nots. They’re attractive
against the silvery leaves with green veins, a
color that shows up well in part to full shade.
Except for very dry soils, it will tolerate most. Growing 12 to 15
inches high and wide, it is
hardy to USDA zone 3, long-lived, and requires little care.
This cultivar of bugloss was
found in a nursery in Michigan as a mutation of ‘Langtrees’. Try
combining it with heartleaf bergenia (Bergenia), Japanese
painted fern, lungworts,
bleeding heart, astilbe, white variegated sedges (Carex) or
hostas, or dark-leaved coralbells.
Recent Perennial Plant of the
Year winners that you might consider too include the threadleaf
bluestar (Amsonia hubrichtii), golden Hakone grass
and hellebores (both generally hardy to zone 5), 'Rozanne' perennial
'Walker's Low' catmint, 'Becky' shasta daisy, 'David' garden phlox,
Japanese painted fern. More on these,
and other winners, can be found online either from the Perennial
Association (www.perennialplant.org) or Perry’s Perennial Pages