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

Blue-needled China Fir

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China Fir's one of the only two conifers you can cut down without fear of killing it.  What's the other?

 

What, stumped already?

 

The only other "stumpable" conifer is a yew.  You can "prune" both right down to a stump with a chain saw and they'll respond with resprouts so quickly you'd think that, for them, being cut off at the ankles was a compliment.  So never fear if you need to confront a yew—or even an entire hedge of yews—that had been abandoned for decades and now needs to be taking up only a fraction of its current real estate.  Rev up a chain saw—or, as I do, hire someone who revs up a chain saw—and have at it.

 

China Fir, Cunninghamia lanceolata, is even happier than a yew with such treatment—delirious, even—because its normal habit is, as you see in these photos, to send up suckers and low-on-the-trunk branches all along.  Felling the tree itself, then, is just the quickest way to encourage them.

 

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Yes, a few of the sprouts appeared only as a result of the stumping.  But the largest ones were already there; cutting off the tree itself just gave them the light and space they needed to really start growing.

 

Stumpability turns out to be a particularly helpful talent in southern New England, where Cunninghamia—even this blue-needled cultivar, 'Glauca', which is, supposedly, somewhat hardier than the straight species—is a challenge in the first place.

 

Oh, not because the tree doesn't bounce right back from its yearly Winter kill.  If Cunninghamia resprouts when chain-sawed to a stump, it will sprout if Winter-killed to a stump, too.  Brown tips on mere branches are nothing.  The real problem is that the tree's other "talent" is to retain its dead needles for years whether they died of old age or were killed prematurely by a nasty Winter.  Without a lot of handful-by-handful grooming to yank out all the dead growth, the tree looks more like a Wookie attempting to camouflage itself by sticking branches of blue spruce in its fur.  Ouch.

 

Worse, the two talents—resprouting and retaining—create a negative synergy:  As the branches repeatedly resprout in response to having their tips Winter-killed each season, the new growth gets denser and then even more dense:  The resprouted growth creates a better and better wind-baffle for next year's round of resprouting, so successive crops of new growth are quicker and quicker, denser and denser.  But meanwhile, the dead needles just keep accumulating.  And they're all through the tree, mostly right into the center, along the main trunks, not just those Winter-killed tips out at the surface.  So access to most of the dead stuff—which is only possible by reaching through the prickly live stuff—gets tighter and tighter as the live stuff gets denser and denser.  Ouch, again.

 

I first thought to capitalize on China Fir 's sproutability by espaliering it against a south-facing wall.  I'd planted a gold-needled cedar, Cedrus libani 'Aurea', very close nearby; in the picture below you can see them as they were earlier this Summer, before the espaliering was to begin.  (You can also see the dense growth that the Cunninghamia had been making in response to the yearly Winter-killing of its branch tips; I'd already cleaned out the dead needles.)

 

cunninghamia-lanceolata-glauca-before-640

 

The plan had been to have the two trees alternate the "rungs" up the espalier:  A horizontal gold limb from the Cedrus, then a horizontal blue limb of the Cunninghamia, then gold, then blue.  And, in truth, this probably would have worked.  Both the Cedrus and the Cunninghamia would have been happy to sprout anywhere from the espaliered limbs that I needed to fill in a bit more, and so I could have trained every rung into a fluffy fat arm.  It would have been, I dare say, the world's first such bicolor as well as double espalier—an espalier duet, a mixed marriage, as it were.

 

But then I realized that I just didn't cotton to blue-needled conifers in the company of yellow ones, let alone in such explicit and intimate array.  Plus, the realization that each of the blue arms would have to be gone over yearly to remove all the dead foliage—which can only be done wearing gloves, thanks to the peculiarly soft-but-sharp Cunninghamia needles—and I just lost the will to bicolor.  (I didn't lose the will to espalier, though.  That never flags.  In the Spring, I'll write on the Cedrus espalier that I soon got underway.  It's thriving and, I grandly predict, on its way to becoming world-famous even just as an espalier solo.)

 

And so, the man with the chainsaw came, the Cunninghamia was stumped, and the Cedrus was left to complete the espalier alone.

 

cedrus-aurea-before-640

 

But what next for the Cunninghamia

 

True to itself, it had resprouted with gusto.  And lovely those sprouts are, too. 

 

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Then if I just let them grow, the Cunninghamia sprouts would soon be right up there with the gold Cedrus.  The solution to keeping the Cunninghamia separate from the Cedrus is to take advantage of Cunninghamia's ability to grow sideways not just upward.  If you were to root side branches, they would continue to grow as side branches: outward not upward.  Even after decades, they would form a tree that's broad and mounded, and without a central leader.

 

True, I don't have a Cunninghamia rooted from a side branch; I've got a regular-habit tree.  It won't ever lose its interest in growing upward by producing the vertical shoots, the leaders.  No problem: I'll prune the leaders off and only let side branches grow. 

 

The leaders are easy to identify.  Of course, they're the truly vertical shoots but also, unlike the side shoots, they have needles all the way around. 

 

cunninghamia-leader-640

 

The needles on the side shoots start out with all-around needling, but soon try to orient themselves to the sun.  They quickly figure out that the best way to do this is if there are only two rows of needles, each facing upright, one on either side of the stem. 

 

cunninghamia-sides-640

 

These side shoots will soon look like so many long and very graceful feathers.  And I'll let them grow out, longer and longer: Because they're growing right from the stump, they'll always be low to the ground.  And because I'm cutting off the leaders, the stump will never be able to grow any trunk from which higher-up side branches could sprout.  There won't ever be any "higher up."

 

With the Cunninghamia becoming more of a groundcover, then, it won't ever be any closer to the gold Cedrus—espaliered higher and higher, wider and wider—than it is now.  With the Cunninghamia branches permanently low to the ground, they're also easier to protect against Winter, too: I could just lay burlap atop them.  Or better, use a cut-to-fit hunk of the wind-baffle fabric that's erected around tennis courts.  It lets light and air through but cuts icy blasts down to, well, icy airflow.  Still icy, but without the sting of the added wind chill.

 

 

Here's how to grow this multi-talented blue conifer:

Latin Name

Cunninghamia lanceolata 'Glauca' 

Common Name

Blue-needled China Fir

Family

Cupressaceae, the Cypress family.

What kind of plant is it

Evergreen coniferous tree.

Hardiness

Zone 6, but only marginal.  Solidly hardy in Zones 7 - 9.

Habit

Vertical and open when young.  Suckers from the trunk base, so free-range trees become multi-trunked and broad. 

Rate of Growth

Fast in climates mild enough that the tree doesn't get a lot of Winter die-back; so fast, in fact, that Cunninghamia can be a good choice to bulk up landscapes that feel too open.

Size in ten years

Growing free-range in ideal circumstances, in a decade Cunninghamia can reach twenty to thirty feet tall and fifteen feet wide.  Ultimately forty to sixty feet tall and, depending on how much multi-trunking has been allowed, twenty-five feet or more wide.  Plants propagated from side shoots—see "Propagation" below—tend to grow widely instead of tall, and as long as any leaders are removed, can be kept in that habit indefinitely; in ten years one might be ten feet or more across but only a few feet tall. 

Texture

At close-range, the branches and needles are very attractive, in two ranks down the branches for a flat and gracefully drooping appeal.  As trees mature, branching and therefore foliage can get denser and denser, so the overall look is more generically "upright and sprucy." 

Grown for

its foliage:  The bright blue needles are thick, like those of yews, but are much longer and come to a surprisingly sharp point.  They're in two ranks down the stems, which also droop gracefully and, on both counts, look like so many feathers.  

 

its habit: Unique among conifers, Cunninghamia becomes multi-trunked unless you prune off the low sprouts from the trunk and the suckers by the trunk from underground.  The trees naturally get wider than a typical single-trunk conifer.  (Trees propagated by rooting side-branches—see "Propagation" below—get even wider.) 

 

its enthusiasm where it can grow in a climate mild enough that Winter-kill isn't a problem (Zones 7 to 9):  Cunninghamia grows so fast you can use it to bulk up a landscape that's too open or too low.  And it's just fine with the steamy heat of Summer even down into Florida:  Cunninghamia is native to China as well as Vietnam and Taiwan.

Flowering season

Late Winter to early Spring, but the inflorescences and cones aren't showy.

Culture

Part shade to sun, in moist, acid, and well-drained soil.  Especially in Zone 7 and into Zone 6, shelter from Winter wind is essential.

How to handle it

In Zones 8 and 9, Cunninghamia is fully hardy, and is very fast-growing.  At the cold end of Zone 7 and down into Zone 6, Cunninghamia needs more and more shelter from the worst Winter winds.  Plant with buildings or larger evergreens to the north and, if possible but at a greater distance from the tree, the south and east as well, to keep the tree in shade in the low Winter sun.  (Winter sun can be especially damaging to foliage that's already suffering in what it finds to be excessive cold, because the heat can cause the leaves to thaw but the roots, still frozen, can't supply the moisture the leaves need to keep from drying out.  This drying out is actually what Winter "burn" is.  In Summer, the sun will be higher, so the trees to the east and south won't shade the Cunninghamia.)

 

In Zone 6, perhaps the best choice is to plant Cunninghamia that are propagated only from side branches:  These grow lower to the ground, almost like groundcovers, which is more protective during the Winter already.  And they can be covered for the Winter with evergreen boughs or wind-baffle fabric.  You can buy them here.

Downsides

Cunninghamia retains dead needles and the little branchlets on which they grow for a long time—up to several years—after they've died, either through Winter kill or because they're at the end of their natural life-span.  If the tree isn't groomed to remove them, it can look quite shabby.  This is especially the case down into Zone 6, where some Winter-kill is normal, and from which the tree recovers well, thanks to its ability to branch even from old wood.  But after several years, the result is such dense growth that the ever-present dead needles and branchlets becomes more and more difficult to clean out. 

Variants

Cunninghamia lanceolata itself is green-needled and not quite as hardy as 'Glauca'.  It's similarly reluctant to drop its dead needles.

Availability

On-line and, in Zones 7 to 9, at retailers.

Propagation

By cuttings in the Fall; side-branch cuttings grow into wide trees with a round crown; cuttings from vertical branches grow upright and more narrowly.  The suckers are particularly easy to root, and will mature with the upright-and-narrow habit.  Cunninghamia can also be propagated by seed, but 'Glauca' is unlikely to come true. 

Native habitat

Cunninghamia lanceolata is native to China.  

 
 
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