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

Fern-leaved Corydalis

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Ferny blue leaves and stems with the same juicy-green color and heft as celery stalks:  If this were a true fern, the stems would be fuzzy, or at least dark.

 

And if it were a true fern, there would be none of these elegant racemes of yellow flowers.

 

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Each has a pair of minute purple inner petals that barely protrude from the pair of yellow outers.

 

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The leaves of Corydalis cheilanthifolia borrow the look of true fern foliage, but when it comes to flowers, let alone seeds, the plant is independent-minded.  See "Quirks and special cases" for its creative strategy to self-seed more widely.

 

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Wherever it appears, Corydalis cheilanthifolia is a gift.

 

 

Here's how to grow this graceful perennial:


Latin name

Corydalis cheilanthifolia 

Common name

Fern-leaved corydalis

Family

Fumariaceae, the Bleeding Heart family.

What kind of plant is it?

Evergreen perennial.

Hardiness

Zones 5 - 8.

Habit

Frond-like pinnate leaves and thick flower stems that seem to be channeling those of celery, and emerge from the base of the plant to form a large rosette.

Rate of Growth

Fast. 

Size in ten years

In full flower, a clump two feet tall—I've heard of monsters of three feet—and about two third's as wide.  For a corydalis, C. cheilanthifolia is huge.

Texture

Ferny, and not just sort-of.  Until it flowers, most viewers wouldn't think it was anything other than a fern.  

Grown for

its flowers:  Tiny down-facing tubular outer petals are palest-yellow, with a just-visible pair of dusty purple petals within, and are held in dense narrow racemes at the tips of bright green celery-like stems.

 

its foliage:  Ferny indeed, forming a large mounding rosette.  The leaves have a particular resemblance to those of Cheilanthes ferns.  Youngest foliage is the same dusty-purple as the petals of the flowers, and matures to blue-green.  The colony quickly burgeons to full size in Spring, and maintains a surprisingly enduring evergreen presence in the Winter. 

 

its toughness:  Ferny doesn't mean frail.  The foliage of Corydalis cheilanthifolia is surprisingly evergreen, and if my experience is any guidance, the species prefers to grow in extremely well-drained locations that would, seemingly, be unable to supply the consistent moisture the thick juicy stems and fern leaves require.

 

its self-directed lifestyle.  Over the years, Corydalis cheilanthifolia is likely to try out locations different than where you had planted it, and can be more evident some season than others.

 

its resistance to browers:  Corydalis is normally ignored by deer.  My garden has a healthy population of rabbits, but they don't nibble either. 

Flowering season

Beginning in early Spring, April into early May here in Rhode Island, and continuing through the Summer.

Color combinations

The muted yellow and purple of the flowers of Corydalis cheilanthifolia, plus the blue of the foliage, allows it to associate with almost anything but orange, red, or pink.  It's a quiet look, and saturated hues that are nearby are likely to look coarse.    

Partner plants


With coloring that's soft, texture that's dramatic and, at least for a Corydalis, dimensions that are positively enormous, fern-leaf corydalis partners more like a fern than a perennial.  The flowers of neighboring plants are secondary but welcome; contrasting foliage needs to be the real show.  

 

Go for leaves that select their gifts from the table that's labeled Large, Shiny, Starkly dark (or light), Smooth-edged, and Leathery.  Shade-tolerant, drainage-appreciating broadleaved evergreens are the best place to start.  So many shrubs: Sarcococca, Aucuba, ElaeagnusMahonia, Ardisia, Skimmia, Prunus laurocerasus, Ruscus, Danae, Farfugium, and Sabal and Rhapidophyllum palms.  The leaflets of holly fern, Cyrtomium falcatum, are so large they look (and behave) like a broadleaved evergreen.  So do the pointed sword-leaves of Aspidistra.  Yes, many of these shrubs and perennials aren't hardy colder than Zone 7, and there are only so many tender things anyone—even me—can grow in containers.  Hardier and, yes, often deciduous partners include hosta, Pachysandra procumbens, Brunnera, and yellow or white-flowered hellebores.

Where to use it in your garden

Corydalis cheilanthifolia is an accent plant with a mind of its own.  I can't recall seeing it used in a clearly intentional way, where precision in spacing was important—or even more informally, where a group of the same plant was the goal.  

 

The growth is full to the ground, and the leaves, stems, and flowers are all a pleasure to study at close range.  Welcome any plants that pop up at the front of the bed.  Leave any that are farther back: More is more, and whatever critters harvest the seeds (see "Quirks and special cases" below) are just as likely to deposit them where you want if you give them more plants to forage from.

Culture

Part sun and good drainage.  Corydalis cheilanthifolia self-seeds, only modestly for me, and has found its most congenial location in a bed of six inches of gravel held in place by landscape timbers, atop the concrete septic tank.  If the gravel bed were in full sun, it would be terrific for hardy cacti; with afternoon shade, apparently, it's the cat's meow for this perennial that looks anything but drought-tolerant.

How to handle it:  The Basics

Plant in Spring, in part shade with good drainage, and let the clumps look after themselves.  If you get around to it, groom the clump in earliest Spring to remove spent foliage, but let the clump enter Winter intact: The plant is evergreen, or has that intention, so appreciates keeping all of its leaves about it as cold weather descends. 

How to handle it: Another option—or two?

Could you translant Corydalis cheilanthifolia to just the location that you want, not the location to which its seeds had found themselves transported?  (See "Quirks or special cases" below.)  In very early Spring, I'd say, before new growth as started.

Quirks or special cases

You can gather seed, which is born in long thin pods, and scatter it (or just the pods themselves) where you like new plants to germinate.  Chances are, however, that animals will redistribute the seed on their own terms.  Each seed comes with an attached snack packet, known as an elaiosome, whose function is to attract and nourish some critter or other, who, in the process, will transport the seed far afield.  Many thousands of plants produce seed with an elaiosome, so the strategy must work well.

Downsides

In my experience, the Corydalis species or cultivars you crave the most—usually, one of the newer hybrids with electric-blue flowers—will also require the most fastidious circumstances.  My rich and often heavy soil is usually unsatisfactory.   

Variants

There are hundreds of Corydalis species to explore, and they are happiest in cooler-Summer climates.  Flowers of these perennials or annuals can be blue, sometimes of dramatic and showy intensity; species and cultivars with white, pink-to-rose, and, as with C. cheilanthifolia, yellow flowers are also available.  Foliage is typically ferny, and can sometimes have tasteful variegation with an overlay of silver or white.  'Berry Exciting' is the loud-and-proud exception, with leaves a solid and bright yellow rivaling that of Dicentra 'Gold Heart'.  

 

Most Corydalis species and cultivars on the market today need partial shade and good drainage to stay active and in bloom.  In such ideal conditions some can flower all Summer long.  If conditions are too hot, sunny, or dry, Corydalis can estivate—become dormant—to escape the heat, returning to activity with cooler Fall weather. 

Availability

On-line and at retailers.

Propagation

By division and by seed.

Native habitat

Corydalis cheilanthifolia is native to China.

 
 
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