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

Today in the Garden of a Lifetime: Mountain Cabbage Tree

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The mountain cabbage tree dropped all of its ravishing blue foliage after the unusually early mid-October frost.  Fine: The tree typically becomes dormant and leafless as it overwinters in the greenhouse.  The surprise is that in December—whose short days and cool greenhouse temperatures bring most tender plants to their lowest ebb of vigor and (frankly) attractiveness—the cabbage tree has resprouted with gusto.  Who'd-uh-thunk?

 

The leaf stems (petioles is the term) are bright green, while the leaf blades themselves are brown-burgundy.  So far, so good—but how much better if the color of the young foliage could be out-and-out burgundy.  I've seen pictures.  I know it happens. 

 

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What conditions dues Cussonia paniculata need to produce young foliage that's living its best life?  Stronger light?  Even deeper coolness?  Greater warmth?  Even less water?  More?  

 

Is new foliage produced after the stress of a frost particularly colorful?  Or is the foliage that emerges in Spring, when the days are longer but the nights are still chilly, particularly colorful?  This is a well-known habit for plants that are dormant in the Winter.  Think of the beautiful purple of the Spring sprouts of peonies and chestnuts.

 

Sources on Cussonia culture—at least all that I can locate—are mum on what, you'd think, would be a topic of interest.  In the years to come, perhaps I'll be able to determine how to help Cussonia flaunt its colors most vividly.

 

The not-yet-colorful-enough foliage is one puzzle to explore.  Another is what's happening at the bottom of those leaves.  Cabbage tree restricts its growth to the top an unbranched trunk for years (looking all the while more like a palm tree than what it actually is, a distant cousin of ivy)—until it doesn't.  After a few years of strictly unbranched growth, there are now a half-dozen sprouts at the top of the trunk of my Cussonia.

 

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This after-the-frost branching out is easy to understand.  The temporary loss of the foliage at the top of the tree stopped its production of a hormone that inhibits the growth of foliage and new stems farther down.  One way, then, to grow a cabbage tree with the tallest possible trunk would be to keep it safe from frost or, more generally, anything that interferes with the primacy of the top growth. 

 

The flowering stems emerge from the tip of the stem, so even when growth isn't stopped by stress, Cussonia trees typically begin to branch after they've become old enough to flower.  A hasty disbud could help a tree continue unbranched growth.  As would pinching off side stems as soon as you notice them.

 

In reality, the real danger, at least with cabbage trees that are growing in pots, is growing too tall to bring into shelter upright.  Once a potted tree becomes five or six feet tall, branching is a good thing.  If your tree doesn't stimulate branching as a result of flowering, you could subject it to a mild frost, as I inadvertently did.  Or you could pinch off the tree's newest flush of young foliage.  Those who are fearless could cut off the tree's entire head. 

 

In all cases, side shoots should appear quickly and even—as here, when short days and cool weather would have normally hustled the tree into dormancy—eagerly.

 

Here's how to grow mountain cabbage tree.

 
 
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