Louis Raymond experiments in his own gardens like

a mad scientist, searching out plants that most people have

never seen before & figuring out how to make them perform.- The Boston Globe

…Louis Raymond ensures that trees can grow in Brooklyn…

or just about any other place where concrete consumes

the dirt and skyscrapers shield the sunshine.- USA Today

 
 

NEW Trips to Take!

Myrtle's easy when the conditions are right.

 
 
 
 

NEW Plants to Try!

Louis tries to capture the exact words to describe the fleeting but deep pleasures to be found in these Summer-into-Autumn incredibles.

 
 
 
 

New Gardening to Do!

Allergic to bees? You can still have an exciting garden, full of flowers and color and wildlife.

 
 
 
 

Plant Profiles

Gotta Get: Cornelian Cherry

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Argh: Another April and I still don't have a cornelian cherry of my own. Instead, I pay homage to this essential species by visiting the pair of them in my local park. Not a cherry at all, Cornus mas is a species of dogwood. The tiny flowers are showy for weeks, and single-handedly carry you and your garden through the weeks between the last of the witch hazels in March and the first of the magnolias and true cherries in April.

 

This plant is essential.

 

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The flowers are a shade of yellow-green that is mercifully less brutal than that of forsythia. Unlike that omnipresent eyesore, Cornus mas in full flower manages to welcome Spring—and sing against a sunny blue sky—without also clashing with the bare stems of all the nearby trees and shrubs that, for reasons of their own, are choosing to snooze through until May.

 

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The display is so prolific and fluffy, and the branches of the plant horizontal enough, that a mature Cornus mas in full flower evokes the display of century plant, which only succeeds in climates that are frost-free. Cornelian cherry is a welcome instance of a species that thrives in cold climates, where century plants are seen only during hot-climate vacations.

 

Here's how to grow cornelian cherry:

 

Latin Name

Cornus mas

Common Name

Cornelian cherry. Cornel is an older form of the word Cornus, the Dogwood genus. The flowers mature to fruits the size and color (although not the taste) of cherries, to which the tree is otherwise unrelated.

Family

Cornaceae, the Dogwood family.

What kind of plant is it?

Hardy Spring-blooming shrub or small tree.

Hardiness

Zones 4 - 7.

Habit

Upright and often multi-trunked, with stiff branches that usually arise very low on the trunks or even sucker from the base. Can read as a large bush or, if a single and clear trunk can be maintained (see "How to handle it," below), a small tree.

Rate of Growth

Medium.

Size in ten years

Twelve feet tall and wide; in time, can exceed twenty feet in either dimension. 

Texture

In flower, fluffy. In leaf, medium. Out of leaf, acceptably twiggy; in my book, the branching is more appealing than that of other Spring flowerers with edible fruit, such as apples or upright cherries.

Grown for

its flowers: Tiny acid-yellow flowers are borne in dense umbels less than an inch across. Despite their lack of size, the overall crop is so prolific—there can be hundreds of umbels on a single large limb, and thousands on a single tree—that the display is striking without being strident. As is typical for early-season flowerers, the display is long-lasting, too: Three weeks is not unusual. The color is especially welcome as a lesson in what to plant instead of forsythia, whose stronger yellow clashes relentlessly with the prevailing browns of the bare limbs of the surrounding shrubs and trees. 

 

its fruit: Colorful but soon eaten by birds (and largely hidden by the Summer foliage, anyway), the fruit are of similar size and profuseness to those of cherry trees, to which Cornus mas is otherwise unrelated. They have similar astringency to cranberries, and so also lend themselves to being used in recipes, such as jam or syrup, that supply plenty of countervailing sweetness. They are rich in vitamin C.

 

its foliage: Variegated forms are highly showy, with solid gold or cream-and-green leaves. They need special handling if they are not to scorch. See "How to handle it: Another option—or two!"

 

its toughness and flexibility: Hardy to Zone 4, and tolerant of average soil and water, let alone continuing Spring frosts, Cornus mas is particularly invaluable in cold climates. Many of the more popular Spring ornamentals, such as magnolias, Spring-flowering witch hazels, corylopsis, and flowering dogwoods, aren't hardy colder than Zone 5. That said, the tree's early season of bloom, and unusual flower color, make it a garden essential in Zones 5 to 7. In short, wherever it's hardy, Cornus mas deserves a place in gardens.

Flowering season

In early Spring, and just when needed: After the last of the witch hazels are done, and before most other Spring-flowering woodies—cherries, magnolias, corylopsis, and even forsythia—have begun. Cornus mas is the last flowering plant of the season to have the multi-week display typical of species that bloom in Winter and early Spring. The entire "season" of the flowers of woody plants that follow it—think of magnolias and cherries in particular—could be just a couple of days.

Color combinations

As shown in the flowers-against-the-sky photo above, the yellow-green of Cornus mas flowers could hardly be more joyful than when seen in the company of blue. White, lavender, burgundy, and yellow are also winning. As with forsythia, avoid siting anywhere that pink-flowering competition, such as magnolias and cherries, could also be in view.

Plant partners

It's as tempting to plant to enhance the unique floral display of Cornus mas as it is to provide additional interest when the plant isn't in bloom. No one cornelian cherry can take advantage of all the options; if there were one ornamental tree to plant in several locations, each with a different goal, this is it.

 

Cornus mas begins flowering when few if any other woody plants are in bloom—which, after all, is one reason the plant is desirable—so opportunities for additional color from flowers are, at first, limited to early Spring bulbs and hellebores. This isn't a debility as much as an opportunity for a few specific and ephemeral triumphs. Why not plant Cornus mas amid as large a sweep of Scilla siberica as you can muster? The starry blue flowers of Siberian squill are at their peak during the Cornus mas season, and the bulb's shade-tolerance means that the "pond" of blue will wash all around the base of the cornelian cherry. If blue-and-yellow is too obvious, underplant with a small fortune of white- or yellow-flowering hellebores. 

 

If you have additional room, also plant Rhododendron mucronulatum in one of its non-pink forms (try 'Easter Bunny' or 'Dwarf Form'), whose lavender flowers will coordinate well with the yellow-green of those of Cornus mas (as well as those hellebores). They are a bit later than those of the squill. The young stems of coppiced Siberian dogwood or any number of willows retain their colorful cold-weather bark while the "cherry" is in flower. The bark of such new growth of Cornus sericea 'Silver and Gold' is greenish-yellow, that of Salix babylonica 'Crispa' is green, of Salix alba var. vitellina, yellow. All need to be planted on the sunny side of Cornus mas.

 

Evergreen partners are always welcome anywhere near deciduous plants that peak when most deciduous plants are still bare twigs. If possible, back Cornus mas with large evergreens to highlight its bright flowers. Or underplant with shade-tolerant evergreens, provided they are hardy enough to look their best in April, even after a long Winter. In Zone 5 and warmer, Cephalotaxus harringtonia 'Prostrata' or 'Duke Gardens' can be at the top of your underplanting list. As long as you don't let it grow so lustily it will overwhelm the entire plant, self-clinging evergreen partners such as ivy or euonymus are another way to bring life and color right up into the lower canopy of Cornus mas. My first choice, at least in Zone 6 and warmer, is always Hedera colchica 'Sulphur Heart', whose yellow-splashed leaves echo the flowers of Cornus mas. See my article on its white-variegated cousin, H. colchica 'Dentata Variegata'.   

 

Gardeners in mild-Winter climates that also enjoy cool Summers have additional options. Oh, to have a large colony of purple-leaved phormium on the sunny side of Cornus mas (whether or not it's underplanted with any of the choices above). The contrast of solid and "swordy" foliage with the fluffy flowers, plus the contrast of the purple foliage with the lime-green flowers: Heaven on both counts.  

 

The phormium and the ivy also ensure interest when the flowering season of Cornus mas is a distant memory. For me, that's June through the end of March. Although the bland green Summer foliage and sturdy branching of Cornus mas cry out for a climbing rose or a clematis, both plants are notoriously ratty looking from hard frost through their return of leaves weeks after the cornelian cherry has finished flowering. It would be a Pyrrhic victory to have flowers spangling the plant in August if it also means tangled stems that scruff of the look of Cornus mas in full flower in April.

Where to use it in your garden 

Cornelian cherry can be effective both at a distance and close-at-hand. The flowers are not fragrant, at least to my nose, so there's no imperative to plant immediately alongside pathways, or close to doorways. If at all possible, site fragrant-flowered cold-weather bloomers such as Hamamelis x intermedia and Mahonia bealei close to the house; you can always rely on Cornus mas for planting farther away, especially in a grove, for long-view and long-lasting excitement. 

Culture

Green-leaved forms handle drier soil and full sun with aplomb. Unless you garden in a cool-Summer climate, variegated forms need richer soil and, even so, afternoon shade.

How to handle it: The basics

Easy! Can be planted in Spring or Fall. As is typical for dogwood species and cultivars, Cornus mas can be purchased both container-grown or balled-and-burlapped, so is often available from small whips to specimen sizes with trunks a couple of inches thick. If planting in Spring, water the first season to ensure establishment; unless your climate or the season is unusually dry, established plants are self-reliant.

How to handle it: Another option—or two!

Prune away low limbs to encourage formation of a clear trunk, and thereby changing the plant's habit from shrub to tree. The branching of some plants can be awkward, leading to the mock-latin name Cornus mess. In all cases, prune when the plant is not in leaf, so you can see the emerging branch architecture more clearly.

 

Suckers can sometimes be a challenge; prune them whenever the force is with you.

 

Forms with colorful or variegated foliage thrive if your Summer weather is cool. Gardeners in northern New England and southern Canada (let alone cool-Summer climates like the coastal Pacific Northwest) should have an easy time growing them. For the rest of us, these fancy-leaved forms can suffer from devastating leaf-scorch if plants aren't sited strategically; I write from painful experience. Plant in rich, well-drained soil, siting where buildings or higher vegetation protects the plant from sun from mid-day onward. High dappled shade all day could be as successful as full shade from noon on. Even with sufficient screening from sun, locations that are breezy might still put the foliage at risk. Experiment with different locations and degrees of shade and shelter from wind and sun to determine where the plant might best tolerate your garden's overall combination of Summer heat, exposure, and humidity.

Quirks and special cases

None.

Downsides

Suckering can sometimes be a problem, especially if your goal is to train the plant into a small single-trunked tree. The fruit is colorful but usually harvested by birds, so don't count on it to provide other than a fleeting show. Unless you're able to grow one of the variegated cultivars—see "How to handle it: Another option—or two!"—the Summer and Fall foliage is usually unremarkable. See "Plant partners" for suggestions on how to bring more interest to Cornus mas when it's not in bloom.

Variants

The fruit of Cornus mas 'Flava' is yellow instead of red; that of 'Alba' is white.

 

The leaves of 'Aurea' are bright yellow in Spring; those of 'Variegata' are green with cream or white edges; those of 'Elegantissima' as well as 'Aureo-elegantissima' are edged with gold; those of 'Tricolor' are gold-edged as well as  flushed with pink. All of these fancy-leaved forms are likely to scorch in full sun, especially if grown in soil that isn't ideally deep and moisture-retentive. Even with such helpful soil, site where they receive afternoon shade—or put them on your wish list for a future life in which you're gardening in a cool-Summer climate.

 

'Golden Glory' is comparatively upright, with a flame-like profile but by no means a columnar one. 'Nana' is dense and fairly dwarf; it would be marvelous to have it grafted on a trunk of the straight species, to form a free-range standard. 'Spring Glow' is more heat tolerant in Summer, and doesn't require as much cold in Winter; it is the cultivar for Zone 7 and even warmer, into Zone 8. 'Spring Grove' is naturally more tree-like, and doesn't sucker.

 

There are many cultivars grown primarily as orchard crops, with fruit that is larger and, sometimes, sweeter. 'Big Fruit', 'Pioneer', 'Redstar', and 'Sunrise' are just the beginning of the possibilities.

Availability

On-line and at retailers.

Propagation

The species reproduces by seed or by cuttings; cultivars will not come true from seed, so are propagated only by cuttings.

Native habitat

Cornus mas is native from southern Europe through Iran to southwestern Asia.

 
 
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