Fall Foliage Beyond the Trees

Perennials and shrubs are easily overlooked when it comes to fall foliage as our focus is captivated by the majesty of trees: giants adorned in cloaks of gold, amber, maroon and chartreuse. The fall foliage “season” at Wave Hill occurs approximately mid-October to mid-November. This month’s Garden Journal entry is not an argument for perennials and shrubs versus trees. Every plant has its place in the landscape; this is a celebration of the often-overlooked fall color of shrubs and perennials.

Let us get some business out of the way: the differences between perennial, shrub and tree. Perennials are generally herbaceous (lacking wood) plants that die back to their roots during the winter dormancy: some familiar species include hostas and coneflowers. Shrubs produce wood, like trees, but generally differ in their form. Michael A. Dirr, a woody plant expert, describes shrubs as having “several stems branching from the ground” whereas trees have a “single central axis, six feet or more from the ground.” However, there is often a discrepancy when it comes to describing individual specimens due to uncountable nuances that vary the plant’s form. Familiar shrub species include hydrangea and winterberry. All three very generalized groups play an important role in the landscape.

Aesculus parviflora (bottlebrush buckeye) kicks off the fall foliage spectacle with a golden glow early in the season. This shrub is sometimes mistaken for a tree because of its size, as it matures to 15 feet tall and much wider by spreading underground suckers. Growing in the Shade Border, Aesculus parviflora is much taller than adjacent small trees of Japanese maple and witch hazel. It also grows underneath Pinus bungeana (lacebark pine), west of the Aquatic Garden, the golden leaves complement the blue-toned, puzzle-shaped bark of the lacebark pine.

Platycodon grandiflora (balloon flower) is a perennial that will color-up suddenly in the middle of the season. Rich, golden-hued leaves exhibit a fleeting red flush and delicate red leaf margins as the leaves senesce (degrade). The leaves are complimented by a maroon central stem, which ties the whole “look” together. In the Wild Garden, balloon flower is interplanted amongst late-blooming, purple-blue flowers of Symphyotrichum oblongifolium ‘Raydon’s Favorite’ (aromatic aster).

Enkianthus perulatus 'Compactus' (dwarf enkianthus) seems to erupt in flames with its brilliant display of red foliage late in the season. This 60-year-old (or older!) plant is exceptionally slow-growing and can be found in front of Glyndor Gallery underneath a tall Ilex opaca (American holly). The compact enkianthus’s dramatic show is contrasted by low-growing black mondo grass (Ophiopogon planiscapus ‘Nigrescens’), the surrounding informal foundation planting and masonry. These elements insist that the viewer’s focus be directed only at this majestic compact specimen.

Two Cotinus obovatus (American smokebush) growing in the Shade Border color up at different times in the season. One, exposed to more sun, turns bright orange early in the season and as it takes on a toasted look, its neighbor on the left picks up where it left off with a slightly muted yellow display later in the season. As with most smokebush specimens at Wave Hill, we coppice, extreme prune, them in early spring before they break bud, which results in the formation of a “stool.” A stool is a stout, short trunk that shoots out vigorous upright shoots in response to hard pruning.

There are so many other shrubs and perennials that deserve mention for their fantastic fall display; put Wave Hill on your calendar for next fall foliage season to see them all!

Notable mentions:

Hydrangea quercifolia 'Munchkin' and 'Ruby Slippers' (oakleaf hydrangea)
plant type: shrub
season color: late
location: Glyndor Gallery

Callicarpa dichotoma 'Issai' (beautyberry)
plant type: shrub
season color: early
location: Perkins Visitor Center

Amsonia hubrichtii (thread-leaf bluestar)
plant type: perennial
season color: late
location: Perkins Visitor Center and Shade Border

Itea virginica 'Sprich' LITTLE HENRY (Virginia sweetspire)
plant type: shrub
season color: late
location: across from Perkins Visitor Center

Fothergilla spp. (witch alder)
plant type: shrub
season color: late
locations: Shade Border, Wild Garden and Secret Garden

Jess Brey,
Ruth Rea Howell Senior Horticultural Interpreter