Cleome hassleriana ‘Violet Queen’, more commonly known as the spider flower is native to South America, and now is proudly displayed in the Scott Entrance Garden. This species’ common name references its identifying features like the long stamens that spill out from the center of its 4 short rounded petals. It was impossible to miss the spider flower’s dramatic blooms when I first walked past, bursting at the seams with petals and stamens flying radially in all directions. The spider flower’s intricate but imposing presence would be a great ornamental addition to your garden! Don’t be fooled by its delicate presence, ‘Violet Queen’ earned its name with its hardy drought resistant and sun loving reputation as well as efficient sowing of seeds. photo credit: M. Arevalo

The Iris domestica is a regal six-petaled flower with rouge dots scattering the orange petals. Located once more in our Scott Entrance Garden, this perennial goes by blackberry lily and can be grown in full sun or light shade. However, the blackberry lily packs a few surprises. Formally  known as the Belamcanda chinensis, it produces a unique cluster of inedible berries that split into pods when it seeds, a bloom that only lasts one day, and a DNA sequence that surprised scientists as well, shifting its taxonomic classification to the genus Iris. Blackberry lily can tolerate several soil types such as rich, sandy, and clay like. This plant blooms in mid to late summer and reaches up to 2- to 3- feet tall. You should consider planting this flower in your garden this summer for its colorful flowers, ability to self-sow, and attract all kinds of great pollinators. photo credit: M. Arevalo

Salvia yangii (syn. Perovskia atriplicifolia) also known as Russian sage, is a perennial native to Central Asia (such as Afghanistan and Pakistan), Southwest Asia and Western Europe. This variety has a beautiful dusty green square stem that hints to its belonging in the family of Lamiaceae and grows 3-4 feet tall with a wide bush base. Russian sage is a favorite of xeriscaping landscapers with its nuanced purples that gracefully pair with other desert plants like sneezeweed, echinacea, and pastel colored gardens while bravely tolerating drought seasons. Overwhelmed by its purple flowers, Russian sage similarly overpowers its surroundings with its fragrant presence, attracting pollinators left and right. Again in our Scott Entrance Garden, I hope you can come and enjoy the thick scent of Russian sage as much as I do during my morning walks into the Arboretum. photo credit: M. Arevalo

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Starting with the common name “monkey puzzle tree,” Araucaria araucana promises to excite and puzzle those unfamiliar with it. A. araucana is a member of the ancient Araucaria genus (of the Araucariaceae family), a group of trees of the Southern Hemisphere, whose lineage dates to the Jurassic period. A. araucana is the most cold hardy and the best known of the genus. A. araucana is endemic to foggy slopes of The Andes between Chile and Argentina, where it often grows at high elevations in well-draining soils derived from volcanic rocks. 

Sharp, scale-like leaves bestow a reptilian appearance to this evergreen conifer. The thick trunk and branches are laden with these scales, which seem to shout “Don’t touch!”.  At the branch tips a dense whorl of leaves surrounds the terminal bud, like a mini agave. The novel scale-like leaves persist for about 25 years before being shed. 

Symmetrical branching with upturned tips creates a candelabra effect on young trees while an egg shape marks the later stages of youth. As plants mature the branches become pendulous, the tips still upturned. Eventually A. araucana develops a tall, slender umbrella form, the trademark look of the species. I love the various habits of this tree, each fun and appealing in its own way.

What’s with the common name?! It seems to be from a prominent British politician who, when showing a specimen to friends, remarked it would puzzle a monkey to climb it. Being very rare at the time, there was no common name, and so “monkey puzzle tree” stuck – or so the story goes. 

A theoretical head- (and hand-) ache for a monkey indeed! The spikes are hypothesized to have been an adaptation against much bigger pests, though: dinosaurs! The species is also uniquely adapted to the threat of fire; the thick bark is highly fire resistant and epicormic shoots may be produced after fires.

As you can imagine, A. araucana makes a bold statement in the landscape.  It can be used as a specimen, accent, or in a grouping. Trees grown in cultivation can expect to grow 20’-30’, and maintain a conical shape.

Naturally occurring trees can grow upwards of 130’ and live 1,000 years. The tall trunks of mature A. araucana have historically been prized for lumber, contributing to species endangerment; Luckily, they are now protected from harvest by law. 

As mentioned before, A. araucana prefers a well-drained soil and a high moisture environment. In its native environment, this tree experiences wet summers and dry winters, a weather trait unique to few places. Because we have no dry season here, well-draining soil is especially crucial to the species’ success. Though A. araucana prefers full sun, it dislikes high and prolonged heat. These preferences make A. araucana a great choice for the Pacific Northwest, but the somewhat picky nature of this tree can make it tricky to please on our side of  the country. 

One of the few places I’ve seen A. araucana grown on the East Coast is Polly Hill Arboretum in Martha’s Vineyard, MA. Here, a group of trees have grown to impressive size, weathering decades of New England winters. This may seem like an unlikely place for this zone 7(8) species to thrive, but the milder temperatures of the island, sandy soil and moist air help orchestrate this botanical feat. 

Inspired by the Polly Hill planting, the Scott Arboretum sought to introduce a group of A. araucana trees. Originally planted in the low-lying pinetum, the trees failed. Recognizing the need for better drainage, a second attempt was made to establish 5 trees at a higher location on Parrish Lawn, near Clothier Hall. Planted in 2019, 3 remain and are approximately 6’ now – fingers crossed!

Visit the Scott Arboretum today to see this one-of-a-kind tree for yourself! And consider exploring the newly renovated Pinetum, where you can find many more unique conifers, new paths, and a grand seating area.

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Few trees have such a distinguishing character as Platanus occidentalis, the American sycamore. Even to the layperson, these grand trees clearly stand out from the rest. The patchwork bark – brown, orange, green and of course, white – make these trees jump out, especially in the winter landscape. The white-tipped branches can be seen from miles away, sharply contrasting the sky and the dull tones of other trees. The bark character and imposing form of these titans make them among the most visually impressive trees anywhere. 

Sprawling giants can be found in farm fields, each with its own distinct character, each instantly recognizable as a sycamore. photo credit: R. Payne-Meyer

P. occidentalis boasts many representatives of the largest trees on the East Coast. The tuliptree, (Liriodendron tulipifera) may give P. occidentalis a run for its money, but P. occidentalis is generally considered the largest tree species native to eastern North America. These behemoths live over 400 years, and continue to grow until death. When open-grown, P. occidentalis trees are approximately equal in spread and height, with astoundingly girthy trunks. Sprawling giants can be found in farm fields, each with its own distinct character, each instantly recognizable as a sycamore. Trees reach 75’-100’ in height and width, growing as tall as 120’ with even greater spread potential. The Pawling Sycamore of Valley Forge, PA has an astounding average spread of 174’.

Few trees have such a distinguishing character as Platanus occidentalis, the American sycamore. photo credit: R. Robert

Many East Coast states have famous sycamore trees like the Pawling Sycamore, revered for their size and growth form. The Buttonball Tree of Massachusetts and the Pinchot Sycamore of Connecticut, are two notable sycamores of New England. The sycamores of Southeastern Pennsylvania may just take the cake though. This region is home to multiple specimens among the largest in North America, and to that end, the world. 

These trees, Platanus occidentalis, are an excellent choice for riparian plantings and naturalized areas, growing quickly and supporting a range of wildlife. photo credit: R. Robert

Here the author is seen in Chester County next to a P. occidentalis tree calculated at 517 points, bested (arguably) by only one other sycamore in Mercersburg, PA with 529 points.  (Score = trunk circumference (in.) + tree height (ft.) + ¼ average crown spread (ft.)). Check out the website for champion trees of Pennsylvania, pabigtrees.com, to learn about these prized sycamores and other awe-inspiring specimens across the state. 

P. occidentalis trees are impressively adaptable, growing from Southern Canada to Florida, westward to Texas. This species wants full sun, and while found almost exclusively in wetland and riparian areas, prefers a well-drained soil. Despite the specificity of naturally occurring plants, P. occidentalis is easily grown in garden and lawn settings. A wide tolerance of pollutants makes P. occidentalis is a great fit for the city or countryside. The actual fit of this tree in the landscape proves more challenging. 

In a residential setting this tree can be more a burden than a blessing, with exfoliating bark, fallen twigs and fruit creating a mess. This, plus an aggressive root system, makes P. occidentalis poorly suited as a street tree. This noble tree is right at home in a park setting though. Here a little messiness can be overlooked and trees may provide shade and wildlife refuge for hundreds of years. P. occidentalis trees are as impressive grown en masse as singly; the collective effect of a sycamore grove is stunning. These trees are an excellent choice for riparian plantings and naturalized areas, growing quickly and supporting a range of wildlife. 

A hybrid species between P. occidentalis and P. orientalis, P. x acerifolia is commonly found across the U.S. and Europe due to extreme adaptability and urban tolerance. photo credit: R. Robert

A hybrid species between P. occidentalis and P. orientalis, P. x acerifolia is commonly found across the U.S. and Europe due to extreme adaptability and urban tolerance. With similar bark and stature to P. occidentalis, it can be hard to tell these two trees apart. This lookalike cousin can be most easily distinguished from P. occidentalis by the fruit: P. x acerifolia fruit usually comes in pairs of two, while P. occidentalis fruits occur singly.

With similar bark and stature to P. occidentalis, it can be hard to tell P. x acerifolia from P. occidentalis. photo credit: R. Robert

Unfortunately, P. occidentalis is susceptible to plane anthracnose from the fungal pathogen Apiognomonia veneta. This introduced fungus found its original host in P. orientalis, though this species and, to a lesser extent, P. x acerifolia, exhibit resistance to it. P. occidentalis trees are often heavily affected by this foliar disease. Though plane anthracnose does not cause serious harm to P. occidentalis, it does cause unsightly defoliation which reduces the ornamental value and growth potential of the tree. The disease overwinters in diseased leaves and cankers on branches. Removal of leaves and branches from the ground nearby helps to prevent infection. Branches with cankers and any dead branches should also be pruned. 

Platanus x acerifolia ‘Bloodgood’ is another cultivar to consider. photo credit: R. Robert

Bizarrely, Platanus trees are considered by some to be the closest relatives of the aquatic lotus genus, Nelumbo. Both Platanus and Nelumbo are likely living fossils, surviving species from a formerly much larger group of related plants. Like its forgotten relatives, P. occidentalis faces the threat of being phased out, at least in gardens. There are so many things I find fun and fascinating about this tree, it is my hope and prayer that this species sees a comeback in landscape use. Lest we forget the majesty of the American sycamore! 

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Thuja occidentalis are typically narrow pyramidal but can develop a broad span with time. photo credit: R. Payne-Meyer

Sometimes plants take a while to grow on me, and sometimes plants I previously disliked I come to really like. Such is the case with the Thuja genus. Woody plant expert Michael Dirr calls Thuja occidentalis (eastern arborvitae) “as common as grass,” and my expectation for T. occidentalis trees in the landscape are typically low as the grass on the putting green. I would submit that the all too common browned out and humdrum spire-type cultivars of T. occidentalis belie the true dignity of this genus. These soft-textured conifers deserve some praise.

The zany low-armed branching of mature Thuja occidentalis specimens is easy to love. photo credit: R. Payne-Meyer

Make no mistake, the untamed and crooked form of a cliffside Thuja occidentalis can be awe- inspiring. I have the greatest respect for the beauty of plants in their natural setting. A straight species T. occidentalis, though irregular, is usually handsome to my eye. Plants are typically narrow pyramidal but can develop a broad span with time. The zany low-armed branching of mature specimens is easy to love. Two grand specimens of the straight species anchor the northeast side of Wharton Hall, showcasing the potential majesty of this tree.

Dark sprays of ferny foliage with cones on Thuja plicata ‘Atrovirens’. photo credit: J. Coceano

When visiting the Pacific Northwest, I was delighted by the grace and dignity of wild-growing Thuja plicata, the western arborvitae. These mammoths are the largest of the cypress family (Cupressaceae), growing to 70’ in the landscape and up to 200’ in the wild. Dark sprays of ferny foliage and a slender conical shape make this plant proud and proper. Dirr calls the foliage the most beautiful of all the arborvitaes. Unlike its cousin T. occidentalis, commercial varieties of this plant hold up just as well in the garden as in nature, and don’t suffer from unattractive winter discoloration. T. plicata ‘Excelsa’ is a smaller selection that shares the grace and dense habit of species, and is great for a coniferous screen in limited space. T. plicata ‘Zebrina’ is a stellar selection offering subtle golden variegation.

These mammoths, Thuja plicata, are the largest of the cypress family (Cupressaceae), growing to 70’ in the landscape and up to 200’ in the wild. photo credit: R. Payne-Meyer

The Korean arborvitae, Thuja koraiensis has dashing foliage as well: blue-green on top and white beneath. The contrast is sharp, but tough to see under the drooping foliage. T. koraiensis is shrubby and grows slowly. The form is broad and gracefully pyramidal. Plants grow approximately 15’ in height, but can reach 30’. T. koraiensis ‘Glauca Prostrata’ is a prostrate form that makes a great substitute for Microbiota decussata, the Russian arborvitae. This form is boosted by an elevated site, such as above a wall, where the silvery foliage can be shown off.

The Korean arborvitae, Thuja koraiensis has dashing foliage as well: blue-green on top and white beneath. photo credit: R. Payne-Meyer

The Japanese arborvitae, T. standishii, is also a smaller- statured conifer, growing a bit larger than T. koraiensis in the landscape, but much larger in the wild. Arched branches with flattened sprays of droopy foliage provide a weeping effect. A hybrid between T. plicata and T. standishii, Thuja ‘Green Giant’, is widespread in the plant industry and is more worthy than the equally ubiquitous T. occidentalis selections. These plants form a perfect conical shape and have an extraordinary growth rate.

While T. ‘Green Giant’ makes an attractive specimen tree, it is most commonly used for screening and hedging. photo credit: R. Payne-Meyer

While T. ‘Green Giant’ makes an attractive specimen tree, it is most commonly used for screening and hedging. This selection boasts better disease resistance than Leyland cypress (×Cuprocyparis leylandii) and better deer resistance than T. occidentalis.

T. plicata ‘Zebrina’ is a stellar selection offering subtle golden variegation. photo credit: R. Payne-Meyer

Thuja sutchuenensis (Sichuan arborvitae) is the fifth and final species of Thuja, a tree rare in horticulture, and nearly extinct in the wild. This is a tree I would hope to see welcomed into the Arboretum collection in the future.

The Japanese arborvitae, T. standishii, is also a smaller- statured conifer, growing a bit larger than T. koraiensis in the landscape, but much larger in the wild. photo credit: R. Payne-Meyer

The aroma of Thuja spp. is a treat as well. The fibrous bark-with strips of tan, brown, red and orange- looks great and smells great crushed. The fruity aroma of the foliage is more noticeably aromatic yet. Add this to the numerous reasons I think this genus deserves another chance!

T. plicata ‘Excelsa’ is a smaller selection that shares the grace and dense habit of species, and is great for a coniferous screen in limited space. photo credit: R. Payne-Meyer

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Sorrel tree is a wonderful, yet criminally underplanted medium-sized ornamental tree. photo credit: R. Payne-Meyer

Where eccentricity meets grace, behold the sourwood. Oxydendrum arboreum, known commonly as sourwood or sorrel tree is a wonderful, yet criminally underplanted medium-sized ornamental tree.  The sole species of the Oxydendrum species, O. arboreum certainly does not lack in uniquity. O. arboreum boasts an interesting growth form, fragrant, bell-shaped flowers, gorgeous fall color, and impressive bark.

O. arboreum is a member of the heath family (Ericaceae), a family composed primarily of shrubs, groundcovers and herbs which thrive in poor, acidic soils. Most commonly found throughout the Southern Appalachians, O. arboreum is native as far North as Western Pennsylvania and as far South as Eastern Louisiana. Though most common in the Southern United States, O. arboreum is quite tolerant of cold temperatures, hardy to zone 4 (-30℉) if sited in a protected location. This tree will often be found growing in oak-heath forests amongst Ericaceous relatives such as Kalmia, Rhododendron, Gaylussacia, and Gaultheria species. O. arboreum trees are tough, but prefer well-drained soil, and will not tolerate heavily alkaline soils, heavy clay, or compacted soils.

O. arboreum typically grows as an understory tree, though mature specimens can become quite large, up to 90’ tall, with the largest recorded reaching 118’! photo credit: R. Payne-Meyer

O. arboreum typically grows as an understory tree, though mature specimens can become quite large, up to 90’ tall, with the largest recorded reaching 118’! Trees tolerate both full sun and part-shade. Cultivated specimens take on an irregular, ovular shape, usually around 30’ tall. Trees I have observed in natural settings are quite inconsistent in their growth form.  Vigorous low branches and abrupt angular deviations of the trunk are common sights on these very expressive trees; a crook in the trunk is a familiar feature as plants twist and turn to find light under the canopy of larger trees.

The leaves of O. arboreum have a droopy habit, lending this tree an aesthetic similar to a small, large-leafed weeping willow. The leaves are finely serrated and dark, glossy green. The sour taste of the leaves bestows the common name sourwood. Fall color is consistently remarkable, as leaves progress from scarlet to crimson; this feature is what I find most impressive about this tree. 

Flower panicles are suspended from the tips of the branches, often even on the leader. photo credit: R. Maurer

Flower panicles are suspended from the tips of the branches, often even on the leader (the upright stem at the top of the trunk), further adding to the overall pendant appearance of this plant. The sweet-scented flowers hang from panicles, and look very much like lily of the valley (Convallaria) flowers. The panicles are long lasting, showing off into the late fall and contrasting beautifully against the deep red foliage. The panicle stem persists after flowers drop as well, giving the appearance of skeletal fingers, a fascinating item of winter interest. The honey of O. arboreum flowers is highly coveted, adding even more landscape and ecological value to this marevelous native tree.

Also not to be overlooked is the bold bark of O. arboreum.  Dark gray, highly fissured bark with broad ridges develops on mature specimens, similar to the alligator hide-type bark of Diospyros or Nyssa spp. The stems of O. arboreum are olive green and red at the tip when young, another pleasing feature standing out from the darker, older bark. 

O. arboreum is a great choice as a specimen tree, or in a woodland garden. With a host of aesthetic features offering four season interest, O. arboreum will stand out even when mixed amongst other trees and shrubs. This tree looks great as both an individual or grown in a group; three or five trees makes for a lovely grouping, each of which will likely have a unique growth form. You can find a group of O. arboreum trees growing on the bank behind Willet’s Hall, a singular specimen flanking the side northeast side of Parrish Hall, and a particularly dashing specimen in the wooded section between Wharton Hall and Dana Hall. 

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photo credit: J. Coceano

For me, the arrival of fall brings a bittersweet feeling. Gone are the long, sunny days, replaced by shorter days and brisk nights, signaling to plants that winter is coming. Despite the sad emotions associated with this shift, a bevy of autumnal delights arise in the garden, giving a sense of awe to a season otherwise marked by endings. Blue, yellow, and white flowers dominate the floral palette, and ornamental grasses come into their moment of glory. With these sights, I find my melancholy mood replaced by joyous wonderment. 

Japanese anemones possess an air of elegance. photo credit: R. Robert

One such fall-flowering beauty I have long been enamored of is the Japanese anemone, specifically Anemone x hybrida ‘Honorine Jobert’, a cultivar offering lovely white, camellia-like blooms. Anemone x hybrida is a group of anemones produced by crossing two or three species of A. hupehensis, A. vitifolium, and A. tomentosa. These species are native to China, though long cultivated in Japan, so the common name of Japanese anemone is somewhat imprecise. Japanese anemones possess an air of elegance which really strikes my fancy. The attractive foliage, tantalizing globular buds, and dignified flower cymes are all delightful to my eye. 

Before the flowers of A. x hybrida ‘Honorine Jobert’ appear, it already holds its own in the garden, offering handsome foliage that plays well with other part-shade companions. photo credit: R. Robert

As the summer begins to fade, A. x hybrida ‘Honorine Jobert’ kicks into high gear, blooming from August through September, showing impressive continuous blooms. These blooms are invaluable by filling the gap before many asters, chrysanthemums, and delphiniums take the stage. Yet, before the flowers of A. x hybrida ‘Honorine Jobert’ appear, it already holds its own in the garden, offering handsome foliage that plays well with other part-shade companions.   

A. x hybrida ‘Honorine Jobert’ mixes well with the similar foliage of Astilbe or Actaea and also bolder foliage such as Hosta. Leaves are trifoliate, palmate, dark green, forming dense, neat mounds of foliage. Plants spread by shallow, creeping rhizomes and can become somewhat aggressive. Easily divided, this plant can be spread to new areas of the garden or shared with friends when a clump becomes too large for your liking. A. x hybrida ‘Honorine Jobert’ looks excellent when planted en masse, so for me the spread of this plant is welcome. Foliage typically grows 2-3’, though when in flower the plants reach closer to 4’ with their tall flower stalks.

The flowers of Anemone x hybrida ‘Honorine Jobert’ feature single to semi-double overlapping white tepals (the petals and sepals are indistinguishable), and abundant orange-yellow stamens surrounding a chartreuse pistil. photo credit: R. Robert

The flowers of Anemone x hybrida ‘Honorine Jobert’ feature single to semi-double overlapping white tepals (the petals and sepals are indistinguishable), and abundant orange-yellow stamens surrounding a chartreuse pistil. As the stamens are lost, the rounded seed head is left atop the flowering stem, like a small pincushion. This, along with the spherical, somewhat egg-shaped buds, provides additional interest to the impressive display of the 2-3” wide, open-face flowers. 

The white flowers do an excellent job brightening up a part-shade garden, accentuating the brightly colored stamens. photo credit: R. Robert

The white flowers do an excellent job brightening up a part-shade garden, accentuating the brightly colored stamens. Flowers are borne on tall stalks high above the foliage, which wave carelessly with the breeze, seemingly unmindful of the imminent arrival of winter. Due to this effect (and I would add a breezy disposition) this plant is sometimes referred to as windflower. 

Anemone x hybrida is not simply carefree in appearance; it is quite versatile regarding growing conditions, performing well in full sun and shade, with light shade being ideal. Moist soil is appreciated; wet, poorly-drained soil is unsuitable. Plants can become stressed by hot, dry conditions, so in the south they should be sited in more shade, while in cooler climates, more sun is preferred. 

The many positive attributes of this anemone have garnered it the honor of the 2016 Perennial Plant Association’s Perennial of the Year. photo credit: R. Robert

Though hardy to zone 4, this plant appreciates a protected setting and/or winter mulch in colder climates. Overall, this plant is very easy to grow and requires little maintenance. The many positive attributes of this anemone have garnered it the honor of the 2016 Perennial Plant Association’s Perennial of the Year. 

A x. hybrida is quite versatile in terms of its garden use as well: it looks great in perennial borders, in a cottage garden, and in modern landscapes. Consider planting it near the front of the garden, where the low, mounded foliage can be appreciated throughout the season. Placement in and amongst other low, foliage plants (actaea, astilbe, hosta) and other fall-blooming plants enhance its beauty. 

A. x hybrida ‘Honorine Jobert’ plants are sited in the part-shade setting of the Metasequoia Allée, where the bright white booms really catch the eye. photo credit: R. Robert

Plants featuring white variegation play well off the dark foliage and white flowers of A. x hybrida ‘Honorine Jobert’, as do ornamental grasses and meadow plants which correspond with its bloom period. A. x hybrida ‘Honorine Jobert’ plants are sited in the part-shade setting of the Metasequoia Allée, where the bright white booms really catch the eye. Consider A. x hybrida and other Japanese anemone types the next time you go plant shopping; you simply can’t go wrong with this plant!

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A native plant brightening up the Arboretum and much of the local landscape is the ever endearing flowering dogwood, Cornus florida. In April and May this small native tree puts on a flowering show throughout much of the Eastern United States.

Interestingly enough, the flowers of the flowering dogwood are quite inconspicuous, tiny yellow-green knobs clustered tightly together between four, large, petal-like bracts. photo credit: R. Robert

Interestingly enough, the flowers of the flowering dogwood are quite inconspicuous, tiny yellow-green knobs clustered tightly together between four, large, petal-like bracts. Flower bracts are available in shades of pink or red in cultivation, though the species color is typically white. These showy floral appendages are undoubtedly what make this tree so treasured, but C. florida has many more landscape attributes.  

In autumn, foliage turns hues of deep red and purple, creating another seasonal spectacle. photo credit: R. Robert

Flowers of C. florida transform into ravishing red fruits in late summer, a favorite of wildlife, though inedible for humans. In autumn, foliage turns hues of deep red and purple, creating another seasonal spectacle.  With age C. florida develops horizontal, tier-like branching and a flattened top, adding unique character and further improving the presentation of this tree in flower. Older trees also develop alligator hide-like bark, which paired with an elegant silhouette make this tree a stand out in the winter too. 

C. florida var. rubra, with reddish-pink bracts that open flat. photo credit: R. Payne-Meyer

Naturally occurring from Maine to Florida, C. florida is typically found as an understory plant, and along forest margins. C. florida prefers rich, moist, well drained soil, and part-shade, though plants can tolerate full sun, and a range of soil conditions.  With great ornamental and ecological value, as well as broad adaptability, this tree is worthy of consideration in gardens in the city, suburbs, and countryside. The versatile nature of C. florida allows use as a specimen, or small grouping in lawns, around homes and patios, in meadows or woodland gardens, grown in sun or shade. 

C. florida ‘Pluribracteata’, whose somewhat cupped double bracts, have a tinge of red at the base. photo credit: R. Payne-Meyer

In the words of woody plant authority Michael Dirr, C. florida is “the aristocrat of small flowering trees,” “the envy of every landscape plant,” and “a superb specimen that will never go out of style.”  Two of my favorite C. florida specimens at the Scott Arboretum grace the lawn outside the Martin Biological Laboratory: C. florida var. rubra, with reddish-pink bracts that open flat, and C. florida ‘Pluribracteata’, whose somewhat cupped double bracts, have a tinge of red at the base. Both of these plants have exquisite form and flowers (bracts) – aristocratic indeed. Plan a trip to the Scott Arboretum today and you can enjoy all these lovely flowers and more firsthand!

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A plant I’m always excited to see in the landscape is Halesia, a genus of trees commonly known as silverbell. While rare in cultivation these trees offer top-notch ornamental qualities throughout the year. I consider the pendulous bell-shaped flowers among the most attractive of any native plant.

Halesia tetraptera can be found at the Scott Arboretum. photo credit: D. Mattis

There are up to four native Halesia species in the U.S., (taxonomical ambiguities are at play) H. tetraptera, H. carolina, H. diptera, and H. monticola.  With most species bearing close resemblance to each other, and overlapping native ranges, it can be hard to tell one species from another.

Halesia diptera var magniflora is another specimen found on campus. photo credit: R. Robert

Though all species are impressive in their own right, the mountain silverbell, H. tetraptera var. monticola (the Arboretum recognizes this as a variety), stands above the others, both literally and figuratively. This tree grows throughout the southern Appalachian Mountains of Tennessee, North Carolina and Georgia. H. carolina and H. diptera inhabit more in the Deep South.

While typically 40-80’ feet tall, H. tetraptera var. monticola is much larger than the H. tetraptera straight species. In old growth forests, the mountain silverbell can reach extraordinary heights, up to 110’. The flowers of H. tetraptera var. monticola are also much larger than those of H. tetraptera and H. carolina, and have white and peachy coloration. Flowers of the mountain silverbell give way to fruits bearing four distinct wings, a visual treat that I enjoy as much as the flowers themselves.

The bark of Halesia trees is also a favorite of mine, strong in appearance, it features gray with darker striations and flattened ridges. photo credit: D. Mattis

The bark of Halesia trees is also a favorite of mine, strong in appearance, it features gray with darker striations and flattened ridges.  Elliptic, obovate foliage varies slightly between Halesia species, and is attractive.

Consider using a Halesia tree at your home, as a specimen, at the rear of a shrub border, against a coniferous backdrop or as an understory plant, as it would be found growing naturally. Silverbell appreciates part to full-sun and moist, well-drained soil.

A pink flowered cultivar, H. tetraptera var. monticola ‘Rosea’ is a particularly dashing variety that can be found in the West Parrish Circle. photo credit: R. Robert

While it may prove difficult to find a specimen of H. tetraptera var. monticola for sale, truly any silverbell is a winning choice. A pink flowered cultivar, H. tetraptera var. monticola ‘Rosea’ is a particularly dashing variety that can be found in the West Parrish Circle. The Scott Arboretum is home to all of the native Silverbellsl; try finding each with the Scott Arboretum navigator, to see which is your favorite!

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Now that the cold months are now upon us, the leaves have fallen from deciduous plants, we turn a keen eye towards our evergreen plants at the Arboretum.  In the simplified winter landscape, the garden becomes a study of form and conifers often take center stage.  Conifers are trees and shrubs which bear cones and needle-like leaves and usually have evergreen foliage.  A specimen evergreen conifer deserving attention this winter is Picea orientalis ‘Skylands’.

P. orientalis trees, commonly known as Oriental spruce, have a refined look in comparison to the larger needled, wide spreading, and heavily pendulous branches seen on many plants of the Picea genus. With small, glossy, tightly whorled needles, small cones, compact and semi-pendulous branching, trees of this species keep a very neat appearance.

The P. orientalis ‘Skylands’ cultivar boasts short, tight yellow foliage, and a graceful form making it an ideal specimen tree. photo credit: R. Robert

The P. orientalis ‘Skylands’ cultivar boasts short, tight yellow foliage, and a graceful form making it an ideal specimen tree. New growth in the spring emerges in a dramatic bright yellow, fading to rich gold with dark green foliage in the plant’s interior. This sharply contrasts with the red cones of spring.

While Picea orientalis ‘Skylands’ can grow in full sun or part shade, foliage color brightens in more sun and becomes softer lime green with more shade.  The color remains an attractive gold throughout the winter.  Like many yellow-needled conifers, the needles of P. orientalis ‘Skylands’ can burn in the hot summer sun and young plants in full sun should receive ample watering. P. orientalis ‘Skylands’ is hardy to zone 4, but a site protected from drying winter winds is recommended in northerly climates.  Exposure to strong winter winds can cause browning of needles.

 P. orientalis ‘Skylands’ has a broad, upright conical form, and a slower growth rate than the P. orientalis species, eventually reaching a size of 25’ tall by 15’ wide.  The smaller mature size and reduced growth rate of P. orientalis ‘Skylands’ make this conifer suitable for the garden with limited space.  Mature specimens will eventually reach a size of 25’ tall by 15’ wide.

While Picea orientalis ‘Skylands’ can grow in full sun or part shade, foliage color brightens in more sun and becomes softer lime green with more shade. photo credit: R. Robert

This conifer is adaptable, performing well in the heat and humidity of the Philadelphia area, but also tolerating temperatures much lower than we experience in southern Pennsylvania.  P. orientalis ‘Skylands’ prefers rich, moist, well drained soil, but such conditions are not essential.  Water needs for this spruce are average, and typical rainfall on the East Coast should provide sufficient moisture. Once established, P. orientalis ‘Skylands’ can tolerate moderate drought and a wide range of soil types, including dry and rocky conditions.  Few pest and disease problems exist for this tree.

A favorite plant of mine for year-round color, I planted P. orientalis ‘Skylands’ in zone 5a Vermont at my family home.  It has grown in full sun and without any winter wind protection.   Approximately 8’ tall after 5 years, it remains in great health.  Consider using P. orientalis ‘Skylands’ as a focal point in your landscape, a planting in the presence of other conifers, and using plants with red, blue or dark green foliage nearby to accentuate the yellow needles. Find our speciemen next to the Faulkner Tennis Courts below the Tree Peony Collection to experience this cultivar for yourself.

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Rhus typhina (staghorn sumac)

By late July, the small flowers have transitioned to eye-catching bright red berries covered in velvety hairs resembling those on a stag’s horn – hence the common name. photo credit: B. Hitz

During the hottest part of midsummer, most native trees and shrubs are not looking their showiest. With spring flowering well past, and fall color still a few months away, many species spend the dog days storing energy from the ample sunlight to produce fruit. An exception is Rhus typhina, commonly called staghorn sumac.

R. typhina is the largest of North American sumacs, reaching up to 25’ tall with a spreading habit. photo credit: B. Hitz

In the Anacardiaceae (sumac) family, R. typhina produces tiny, greenish-yellow flowers in cone shaped panicles from late May to mid June. By late July, these small flowers have transitioned to eye-catching bright red berries covered in velvety hairs resembling those on a stag’s horn – hence the common name. As the season transitions to fall, its compound, serrated leaves turn a brilliant mix of yellow, orange, and red. The fruit continues to darken to blood red through fall and winter and is a valuable food source for many overwintering songbirds.

R. typhina is the largest of North American sumacs, reaching up to 25’ tall with a spreading habit. It spreads aggressively through underground rhizomes and needs a large, open space where it can form colonies. It does well in a broad range of soil types as long as it is in a well drained area. R. typhina is a pioneer plant that appears along roadways, vacant city lots, and other disturbed areas. Because of its similar leaf pattern and similar eagerness to grow in difficult conditions, it is often confused with the non-native and invasive Ailanthus altissima (tree of heaven).

R. typhina is a great addition to a native woodland restoration project because of its ability to attract wildlife during multiple seasons and its potential to outcompete invasive species. photo credit: B. Hitz

This vigorous sumac is best used in informal gardens and naturalized areas. It makes a great roadside screen because of its tolerance of salt spray and its willingness to grow in dry, disturbed areas. The erosion controlling potential is demonstrated on the steep embankment along Chester Road in front of The Inn.

Moreover, R. typhina is a great addition to a native woodland restoration project because of its ability to attract wildlife during multiple seasons and its potential to outcompete invasive species.

LacetteTM is a compact growing selection with a lacy appearance. photo credit: R. Robert

At the 2019 Scott Arboretum Selections: Fall Sale on Saturday, September 14, we will have Rhus aromatic ‘Fine Textured Compact Select A’,  Lacette^TM fragant sumac. Like R. typhina, the fragant sumac is known for its toughness in the landscape as well great fall color. Lacette^TM  is a compact growing selection with a lacy appearance. A great native selection for woodland restoration or erosion control.

Try these sun loving plants in your garden.

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