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

Oregon Grape Holly

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Week by week through the Winter, the buds of Mahonia bealei consider whether the weather is warm enough for them to open.  Even though this is the mildest Winter in years, early March is still too soon. 

 

There's progress from a month ago, when the buds were smaller, and gave no hint of the yellow flowers to come.

 

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Perhaps by April?  Eventually, flowers do come to fruition, so to speak:  Here's a patch of seedlings from last year. 

 

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I'll transplant them soon, to test some other locations in the gardens that might please Mahonia even more.  See "How to handle it" for tactics to establish vigorous grape-holly at the cold end of its hardiness range.  Happier plantings will bloom earlier.  February or March, please?  Winter gardens need all possible ornament.

 

 

Here's how to grow this eccentric evergreen shrub:


Latin Name

Mahonia bealei

Common Name

Oregon Grape Holly

Family

Berberidaceae, the Barberry family

What kind of plant is it?

Broad-leaved evergreen shrub.

Hardiness

Zones 5 - 9.

Habit

Clumping and upright.

Rate of Growth

Fast in mild climates; slower in colder climates. 

Size in ten years

Six to eight feet tall and almost as wide.  Taller in deeper shade; shorter with more light.  Smaller in colder climates.

Texture

Sculptural and modernistic if growth is kept sparse enough to be appreciated stem by stem.  Full and even heavy if the shrub is growing in mild enough climates where there's no Winter damage, where Mahonia can grow so thickly that it becomes as wide as a rhododendron.

Grown for

its foliage.  Unique in shrubs hardy into Zone 5, Mahonia foliage seems a mash-up of palms and holly, with evergreen palm-frond-like leaves composed of painfully-spined leaflets.   

 

its habit.  Tall cane-like stems hold only a few fronds, I mean leaves, in a whirl at the tip.  Shrubs in milder climate develop so many stems that they crowd each other, forcing outer branches to lean outward. 

 

its flowers.  At the tip of the canes, multi-fingered clusters of greenish buds open to small, pendulous yellow flowers.  The buds themselves are showy—thank goodness, because they can be present for months until the shrub senses that, finally, the cool weather is just warm enough for the flowers to open. 

 

its fruit.  The flowers mature to round fruits that are the color and size more of blueberries than grapes.  Yes, there are grapes that are this small, but most are much larger, and are often of unrelated colors such as purple, ebony, or green.  But blueberries are always blue, and always, roughly, the size of the fruits of Oregon grape holly.  Would Oregon blueberry holly be any more confusing a name?  If you can harvest them before the birds do, Mahonia fruit is tart but delicious.  Surely there's a jam or chutney recipe they can embellish.     

 

its toughness.  When well-established, and growing in a climate and exposure—see "How to handle it" below—where the shrub doesn't get slaughtered by cold each Winter, Mahonia bealei needs little or no Summer water, is avoided by deer, and even after years of inattention, looks not just presentable but exciting, .  

Flowering season

Winter in Zone 7 and warmer; late Winter and early Spring in Zone 6 and colder.

Color combinations

The green foliage and the blue fruits go with anything.  The yellow flowers in Winter and early Spring are—like all cold-weather blooms—so welcome that concern that they might need to be coordinated with their surroundings is almost churlish.  But if there are choices to made in what to plant with Mahonia, well, then, why not be thinking about some inspired partnerships with its yellow flowers? 

 

They'll be in good company: Most cold-weather flowers—especially those of shrubs and small trees whose blossoms would be at a similar height—are white or yellow, sometimes mixed with green:  Corylopsis, Stachyrus, Garrya, Cornus mas, Hamamelis, Forsythia, Jasminum, Edgeworthia, Abeliophyllum, and Pieris.  Winter-blooming bulbs—Galanthus, Eranthis, Iris, Daffodil, and Crocus—are usually white or yellow, too—or, just as good with yellow, blue or purple.  And then there's the infinity of Helleborus species and cultivars with flowers in green, white, yellow, or burgundy. 

 

Just keep Mahonia far away from the few plants whose cool-weather flowers can be pink—Prunus mume, Viburnum bodnantense 'Dawn', and all the early-season pinks of weeping cherries, magnolias, hyacinths, and rhodies and azaleas.  See "Partner plants" for specifics.

Partner plants


Thanks to its uniquely scuptural and evergreen foliage, and its potential size, Mahonia bealei is a year-round star in any garden that's shady enough.  Finally: a plant that doesn't merely tolerate shade; Mahonia requires it. 

 

The foliage is so striking in the Winter garden that it's a "category killer" for most other broadleaf evergreens, whose unarmed and sometimes droopy foliage would look flabby or merely heavy in comparison.  Instead, combine with deciduous shrubs and trees (choose from the hordes in "Color combinations" above) or even herbaceous plants; add evergreens only if their foliage is distinctly different in color, size, and texture.  The dark needles of Taxus are too similar in hue, and are as glossy as the Mahonia leaves.  The feathery foliage of Thuja and Thujopsis has no shine, and is either a contrasting bright green or, in the cultivars, an even more contrasting bright yellow or cream.  Cryptomeria, Cedrus, and Juniperus would also be good evergreen partners for the same reasons.  The challenge would be in combining these sun-loving evergreens with the shade-requiring Mahonia.  If you're using tree-sized versions of any of the conifers, they themselves can shade the Mahonia.  A grove of Cryptomeria underplanted with Mahonia would be a triumphant mixture of texture, color, and form.  As would be a deodar cedar with Mahonia planted to its northeast. 

 

Mahonia is so strong an evergreen that, even though the shrub is vase-shaped, with a comparatively small foot-print and lots of area under the ever-spreading canopy, it still doesn't need an evergreen groundcover.  Pachysandra, ivy, vinca, sarcocca:  All would be too heavy in combination with the Mahonia foliage.  The bright-green fluffiness of woodruff, Galium odoratum, would be heaven April through frost, and even in Winter it retains a stippled presence above-ground.  Huge but fragile leaves of hosta would be another good warm-weather contrast, as long as they don't get shredded by contact with lower foliage of the Mahonia.

Where to use it in your garden

Along with Aucuba and cherry laurel, Mahonia is one of the top go-to shrubs for deep shade, thriving where rhododendrons, box, and holly quickly fail.  If the shade is created by buildings, so much the better: Mahonia is at its most striking when backed by a wall.  If there can be a walkway or terrace nearby, you can enjoy the Mahonia flowers without walking across Winter-wet grass. 

 

In climates where Mahonia is solidly hardy without any of the tricks and tactics in "How to handle it" below—Zone 7 and wamer—Mahonia can be an anywhere-in-the-garden filler, or even planted en masse as an informal hedge.  But where its establishment and vigor is a welcome surprise—Zone 6 and colder—this shrub is a star, and, as long as it gets the Winter shelter it needs, demands your most prominent siting, and your most important setting.  

 

Mahonia is particularly helpful in city gardens, which usually must contend with shade, and also must look their best when owners are not at their houses at the shore or in the mountains: All Winter long.  For non-gardeners—most clients, in my experience—the striking foliage and fragrant cool-weather flowers of Mahonia are a new thrill, and one that makes the garden designer seem like a wizard in their eyes, too.

Culture

Morning sun and afternoon shade, or part- to heavy-shade all day.  Almost any soil with decent drainage, although growth is quickest and thickest in loose rich soil, the same as you'd provide for rhodendendrons.

How to handle it:  The Basics

In Zones 7 - 9, plant in Spring or Fall; plant only in Spring in Zones 5 and 6.  With Fall planting, the shrub is established nicely by the following Summer; in shade, Mahonia is drought-tolerant.  With Spring planting, take care to provide enough water to ensure survival through the hot and often dry weeks to come. 

 

Mahonia bealei is almost bullet-proof in Zones 7 and warmer, but in Zones 5 and 6, it can look miserable without Winter-wise siting and care.  Good drainage for both water and air are essential.  Plant on a slope, no matter how gentle, and don't block down-hill airflow, either.  A location with little or no wind is normally a help to protect the foliage from wind-burn during cold weather, but not if this means the shrub is sitting in a low pocket, where the the heaviest—and therefore the coldest—air will collect. 

 

Consider all possible buffering of wind.  Thick growth nearby and overhead is more helpful than walls or buildings, which, when they deflect the wind, often ramp it to even stronger force.  If possible, site the shrub to the North of a building or tall evergreens, so that it receives little or no sun in Winter.  Spray with antidessicant the first few Falls,and again in January or February, when there's a sunny day and the temperature's above 40.  Mulch in late Fall for the life of the shrub, to help the roots' ability to absorb water even in freezing weather.

 

All of these precautions notwithstanding, I have seen immense Mahonia shrubs in Zone 5 and 6, planted in violation of any of this advice, and yet clearly happy for decades.  I have also killed more than a few when trying to establish them in conditions other than what I recommend. 

How to handle it: Another option—or two?


Mahonia bealei is very happy to produce only a few stems, growing to six feet and higher, and leaning out, hopefully, toward the most modest patch of sun.  Although the shrub can look wonderfully sculptural when growing tall and sparse in front of high masonry walls—where it performs the same modernistic dance that dracaena would do in milder climates and with more sun—it's more often the case that you'll prefer additional stems and shorter overall height.  Cut too-tall stems back by half; they will produce a couple of side branches.  Cut down to the ground other stems that are too sparse, too askew, or (lucky you!) too numerous.  Mahonia is obliging about producing new shoots from the base after you provide some encouragement.

 

You could also avoid the need to ponder the handling of this or that branch by cutting the entire shrub down to a couple of inches.  Unless you're gardening in really mild climates, where "Winter" is actually the growing season after the enforced dormancy of a hot and dry Summer, prune Mahonia shrubs to the ground only in the Spring.  Show them extra kindness afterwards, with some extra water and a top-dressing of your juiciest compost.  Then they'll sprout more quickly and more lushly. 

Quirks or special cases


By Spring, it's not unusual even for happy Mahonia shrubs to need some grooming.  Individual leaflets may have turned red or brown during the Winter although the rest of the leaf has remained in good condition.  The only way to pretty things up is to groom leaflet by leaflet.  If you wait until warm weather, your bare fingers and forearms will be tortured by the fierce spines of the foliage.  Instead, add this task to your to-do list for when crocuses are in bloom, when it's still chilly enough for you to be wearing a heavy overshirt and light gloves anyway.

 

Wield your tiniest pruners, with needle-nosed blades, so you can snip at just the right angle and with just the right access.  Bonsai shears are perfect; I've even used old nail scissors.  

Downsides

If it gets too much sun, Mahonia bealei lets you know quickly: The leaves bleach to a sickly yellow-green.  Alas, the condition isn't reversible.  Provide more shade, or transplant the shrub to where it gets more shade.  When there's enough deep-green foliage to spare, cut off the bleached leaves.

Variants

There are scores of Mahonia species worldwide, plus hybrids and cultivars; there are almost a dozen-and-a-half species native to western North America alone.   

 

M. aquifolium has gentler foliage, and is a wide-spread groundcover in the Pacific northwest.  Although widely available in the Northeast, it rarely succeeds unless snow cover is so regularly deep and long-lasting that the shrub is, essentially, buried for the Winter.  If you garden in eastern Canada, consider planting it. 

 

M. repens is, appropriately, shorter, and is a popular drought-tolerant and deer-proof groundcover throughout the Rockies to the West Coast; it's so hardy that it's naturally occuring in North Dakota.  It needs excellent drainage Winter and Summer to thrive in the East, but is even tougher than M. aquifolium—and also lower, so is more readily buried under snow.

 

M. nevinii and a separated-at-birth twin from the barberry family, Berberis trifoliolata, both have narrow and exceptionally spiky leaves.  They are dry-climate natives, thriving in the southern Rockies and into west Texas, and could handle the humidity and year-round moisture of gardens farther East only with perfect drainage.  They're on my planting-list for some new elevated beds that will be fllled largely with sand and gravel—a habitat that's the antithesis of my garden's usual circumstances of rich soil and a high water table.

 

There are several hybrids of M. bealei with M. lomariifolia.  These M. x media grape-hollies have much more delicately-textured foliage, larger and sooner-to-peak clusters of flowers, and larger size overall.  They are not reliably hardy colder than Zone 7, and even there need careful siting.  'Charity' could reach fifteen feet instead of the eight to ten that would be tops for M. bealei itself.  The new foliage of 'Winter Sun' is a contrasting bronze.      

Availability

On-line and, where the species is easily hardy, at retailers.

Propagation

By seed.

Native habitat

Mahonia bealei is native to the Pacific Northwest. 

 
 
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