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…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

 
 

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Myrtle's easy when the conditions are right.

 
 
 
 

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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

Chinese Tulip Tree

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The most exciting foliage of any hardy woody?  My vote is for the Chinese tulip tree.  Its leaves are enormous—as long as your forearm—and sing a season-long medley of burgundy, lime green, pink, and orange.

 

The tiny new leaves are eggplant, putting the lime-green veins on maximal display.

 

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The huge protective bud-scales from which each leaf emerges are even brighter than the leaf's veins.  Not just green, they're acid-yellow.  Could the contrast with the burgundy leaves be any better?

 

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The matte surface of the leaves causes water to bead up like jewels, giving a display that was already ravishing yet another kind of sparkle.

 

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As long as you do a bit of confident pruning each Spring, this amazing display continues far into the Summer.

 

 

Here's how to grow this extraordinary tree:

Latin name

Liriodendron chinense

Common name

Chinese tulip tree

Family

Magnoliaceae, the Magnolia family.

What kind of plant is it

Deciduous tree.

Hardiness

Zones 6 to 9.

Habit

Single-trunked and strongly upright, like the native Liriodendron tulipifera.  See "How to handle it" for a strategy to grow this tree as a shrub.

Rate of growth

Fast.

Size in ten years

In Zone 7 and warmer, twenty to thirty feet tall and half that as wide.  Ultimately, the size of native tulip trees: eighty feet and taller, potentially to one hundred and thirty.  Slower and shorter in Zone 6.

Texture

Lively.  Free-range trees are typically open, showing nice intervals of branch and trunk.  Trees that are pruned (See "How to handle it: Another option—or two!") to a more compact habit are so dense as well as full that they could also function as warm-weather screening.

Grown for

its foliage, which is similarly shaped to that of native tulip trees, but is strikingly larger.  Leaves can be as large as eighteen inches—as long as from my wrist to my elbow—and as broad as twelve.  Mere size, though, is the least of the show.  Leaves emerge a burgundy deep enough to do any smokebush proud.  It soon lightens to a color that, in direct sun, is a powder-burgundy blush, but which can glow anything from pink-grapefruit to orange when back-lit.  Soon it matures to green.  Marvelous!  Because neighboring leaves on the same stem will be either younger or older, they will each be at a different phase in coloring.  Stunning!  The show is enhanced even further by the contrast with each leaf's bud-scales—the protective sheath from which the true leaf emerges—which remain acid yellow-green.  Staggering!

 

Further, rainwater beads on the leaves, and after a shower the foliage is simply magical.  This beading is known as the "lotus effect," where it was first observed, and is thought to facilitate leaf hygiene:  Dirt and pollen become dissolved in the passing beads of water, which then, conveniently, dispose of the mess by rolling cleanly off the leaf.

 

See "How to handle it: Another option—or two!" for strategies to make the foliage display even more breathtaking.   

Flowering season

Late Spring, but not colorful like those of Liriodendron tulipifera.  With soft green petals, the flowers are unlikely to be noticed at all, especially because the free-range tree can be so tall that they aren't visible from ground level.  Liriodendron chinense is grown for its foliage. 

Color combinations

The burgundy, powder-purple, and acid-green of young foliage, plus the mid-green of mature, make up a palette that is strong, sophisticated, and fully satisfying in itself.  Unless any additional colors are only reinforcing these, they are likely to look overly busy, if not disturbing.  Choose among paler yellow than acid-green, or cream—or a medium-dark burgundy, which will be more saturated than the powdery hue that adolescent foliage adopts before changing to all-green. 

 

"Medium dark" burgundy is lighter than the near-eggplant of this tulip tree's very youngest foliage, so contrasts with it as well as with the adolescent, thanks to doses of oxblood or garnet.  These red hues become evident in the leaves of purple-leaved smokebushes when they are back-lit by the sun.  Nonetheless, I wouldn't go so far as to add such red tones in a pure form—with, say, cultivars of begonia or caladium.  (Not least, the large leaves and density of these plants' growth would be a leaden repetition.)  See "Partner plants" below.   

Partner plants

With the remarkable foliage and self-contained color palette of Liriodendron chinense, its neighbors need to be supportive, even secondary.  Partner plants take the cues from this tree, not the reverse.  Embrace contrasts in foliage size and form more than contrasts in color (whether that color is provided by foliage or flowers).  Because all forms of Liriodendron appreciate soil that doesn't become too dry, ferns could be an inspired underplanting.  If you're growing Liriodendron chinense as a full-sized shade tree, site it amid as large a sweep of ferns as you have room for.  The lighter foliage of Dennstaedtia punctilobula would be as welcome as its fizzy texture.  For ferny foliage that is concentrating on the burgundy side of the tulip tree's palette, plant a purple-leaved Japanese maple, but the more cut-leaf the better.  If I were growing my tulip with more room at the front, I might consider adding Acer palmatum 'Red Pygmy'

 

Evergreens with foliage that's dark and small would also be welcome.  My Chinese tulips are grown as shrubs, and are backed by a tall yew hedge.  Just as successful would be to underplant a free-range tulip with free-range yews; they could look just as good with ferns as with the tree itself.

 

Grassy foliage is another good idea, as long as the grass receives the sun it needs.  My tulips are very near a horse trough full of pots of papyrus; because the tulips are pruned as shrubs, there's no dange that their eager growth would shade out the sun-loving papyrus.

 

Leaves that are variegated in yellow or cream are usually a lively addition.  I set a potted variegated Clerodendron trichotomum next to my tulips for the warm months; for the ultimate in hardy variegated partnering, consider Aralia elata 'Silver Umbrellas'.  Be careful of foliage variegated with purple, which might compete with the multi-tone effect of the leaves of the tulip tree.

 

Neighbors with large foliage of simple shapes would compete with the leaves of the tulip tree if the foliage is at all similar in scale.  So I don't recommend underplanting Liriodendron chinense with any hostas, as tempting as they are, color-wise, for bringing a wallop of acid-yellow right up to the trunk of the tree.  But you can double-down with style by adding a tropical or two, whose foliage can be orders of magnitude larger than that of the tulip.  Go lighter with Xanthosoma aurea 'Lime Zinger'; go darker with Ensete maurelii.  

 

I hesitate to add flowers to any composition including Liriodendron chinense.  They're liable to look like chintz curtains on a castle.  Small flowers in colors that don't stray from the colors of the tulip's leaves are one possibility.  The flowers of Nicotiana langsdorphii are lime-green; a huge pot of it would be a thrill.  Or consider dusky purple flowers of a Clematis viticella cultivar, say, 'Royal Velours', which would emphasize the foliage's dark tones in late Summer, when they do, admittedly, wane.

Where to use it in your garden

Liriodendron chinense is such a showy plant that it needs siting where its unique charms can be easily appreciated.  The fast-changing details of the developing foliage demand close-range viewing, and so I recommend growing Chinese tulip as a shrub, not a free-range tree.  Full-size, the foliage details could only be appreciated if you had a bucket-truck.  Because the foliage is particularly showy when back-lit, choose a site that permits either west access right up to the foliage, so you can catch morning sun through the leaves; east access, to catch afternoon sun; or, ideally, north access, so you can enjoy back-lit foliage all day long.

 

My shrub-sized Liriodendron is sited in a comparatively narrow bed alongside my terrace, so there's no difficulty in savoring each element of its performance.  The bed is along the east side of the terrace, with a high yew hedge behind, so I can only enjoy back-lit foliage in late morning, when the sun is above the hedge, but before it's directly overhead. 

 

Because the new foliage is formed, by definition, at the very tips of new growth, and the most colorful new growth is, usually, at the very top of the tree, Chinese tulip is best handled so that it forms the maximum amount of new growth at the lowest elevation:  From zero to six or eight feet high.  Given that a free-range tree could become ten times as tall or more, confident pruning is essential.  See "How to handle it:  Another option—or two!"      

Culture

As for the native tulip tree, Liriodendron tulipifera: Any regular  soil.  Full sun.  Not drought-tolerant, though.  As with plane trees, which are every bit tulip trees' equal in overall bulk and "mammothity" of limb, this is a tree for what farmers call "rich bottomland," the flat and low-lying open areas in the flood plains of rivers.  These have just the conditions the tree thrives in:  Deep soil, ready access to the ground-water, and, thanks to the periodic flooding, the absence of many of the sun-hungry but drainage-demanding tree species that could shade out the tulip tree in a more generic forest environment.  That said, plane trees are the ones that are delirious right along the river bank.  Tulip trees are happier farther back, on slightly higher ground.

How to handle it: The Basics

In Zone 8 and warmer, plant in Spring or Fall; in Zones 6 and 7, plant in Spring.  The tree grows quickly, so there's no point in purchasing large-size specimens.  And because the best foliage performance is gained by severe Spring pruning—see "How to handle it: Another option—or two!" below—much of the bulk of a large-size specimen would be removed, anyway. 

 

Take care to provide enough supplemental water until the tree is established.  In appropriately deep and moisture-retentive soil, the tree is self-reliant after establishment.  Trees that are sited where free-range growth is the goal need little or no formative or maintenance pruning.  If pruning should ever become necessary, do it in early Spring. 

How to handle it: Another option—or two?

Growing Liriodendron chinense as a large shrub will enable the most detailed appreciation of the tree's remarkable foliage.  Happily, the same handling also encourages maximum production of the colorful new foliage, and over the longest portion of the growing season.  The leaves produced as a result of the pruning needed to maintain the tree as a shrub are more likely to be unusually large, too.  

 

Let just-planted trees establish without pruning for a season or two; Liriodendron chinense grows very quickly when established but, in my experience, can dawdle as a youngster.  Early the next Spring after the tree has experienced its first season of eager growth, reduce the height of the main trunk by half, or more if there are still side branches below where you've cut.  Prune the remaining side branches back by half as well.  After new growth has begun to emerge, revisit the tree in hopes of tipping back pruned branches even farther.  The goal is to encourage new growth to emerge from as low down on the branches and trunk as possible. 

 

Let the new growth develop on its own for the rest of the season.  Established trees can produce new shoots that are five and six feet long, but even first-timers will respond with shoots of a couple of feet.

 

Every Spring thereafter, cut back all of last season's new shoots to just above the lowest bud.  After several years, this permits the plant's overall size and height to increase slowly, but relentlessly.  To counteract this, prune more radically every three to five years, by removing a couple of feet of "old growth" from the top of the shrub, and also by shortening the side limbs.  Keep in mind that only the new growth at the very top of the bush maintains production of the most colorful new foliage into the dog days of July and August.  And by July and August, that new growth may already be four or five feet long.  If that growth emerged in Spring from leaf buds that were already four or five feet above ground, by August you'd need a step-ladder to see current new growth eight or ten feet high.  Next season, I'm going to experiment with cutting new growth back by half in early July, in hopes of encouraging side branches with still more new growth tips, and all at lower altitude.

Any (other) quirks or special cases?

None.

Downsides

If only Liriodendron chinense were hardier than Zone 6.

Variants

Hybrids with Liriodendron tulipifera are known, and have intermediate characteristics.  Given that this would mean a reduction in the appeal of the foliage of the pure L. chinense, their value, other than for increased hardiness, would seem to be limited.  'J.C. Raulston' is a cultivar of L. chinense alone, and is reported to have more deeply-indented leaves.  I look forward to coming across it. 

 

Availability

On-line and, rarely, at "destination" retailers.

Propagation

By seed.

Native habitat

Liriodendron chinense is, indeed, native to China.    

 
 
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