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: Gold Cone Juniper vs. Sky Pencil Holly: Tall & Toppled

The weight of nearly two feet of snow is a test for any plant that normally stands tall. Only those with short side branches angling downward from a single and strong central trunk are completely storm-proof.


'Gold Cone' juniper doesn't really have much in the way of any trunk; its habit is tall and columnar only because its basal branches grow vertically. To hold everything in place, I had spiral-tied the shrub with twine way back in December.




But another shrub of similarly vertical habit has shown that such twining isn't, in itself, enough.


Take a look at the candy-cane shape at the back. It's 'Sky Pencil' holly and, when upright, it's over eight feet tall. The holly also develops its columnar shape by the tight vertical growth of its basal branches; as with the juniper, there's little if any actual trunk. But the juniper remained standing after this historic blizzard, and the holly is bent in half. Spiral-twining certainly didn't keep this shrub vertical in the face of heavy snow.




What's the difference?


One key is the flexibility of each shrub's individual branches. Those of the holly are much more willowy. The candy-cane contortion looks damaging but, thanks to that same flexibility, Ilex crenata 'Sky Pencil' will regain its verticality when released from the snow.


Another challenge for 'Sky Pencil' is that its foliage is no help in holding its branches in place. The small leaves are smooth-edged and round—and they're comparatively shiny because they have a waxy coating. In every way short of secreting actual lubricant, then, the leaves provide a slippery coating to the branches, making it easier for one to slide past another, and for the entire sheaf of tied-up branches to shift.


During a heavy snowfall, even the slightest lean can begin a downward synergy: Snow can stick just a bit better to the side of the shrub whose slant is facing upright, and less easily to other side, whose slant is facing downward. More snow brings more weight, which exacerbates the lean and, therefore, only increases the ability of still more snow to come to rest on the shrub's slanting side. More snow, more lean = More lean, more snow. If the 'Sky Pencil' weren't tied together, individual branches would quickly splay outward. When it's all tied together, the shrub still leans—but this time, all in the same direction.


In both foliage and branch, Juniperus communis 'Gold Cone' has the advantage. Its branches are less willowy and more rigid. This gives the sheaf of branches much more resistance to even the start of a bend, and so better avoids the start of downward synergy. And, perhaps even more important, the foliage has none of the "lubricating" qualities of that of the 'Sky Pencil' holly. Its surface is dull instead of shiny, so it's not as smooth or slippery. It's also needly and scratchy, and so dense it feels like—and acts like—sand paper. With the branches tied tightly together with twine, it's as difficult for them to shift as it would be if you pressed two sheets of sandpaper tightly together and then tried to slide them past one another.


'Gold Cone' is never likely to need more than the spiral-twining. Even with the twining, 'Sky Pencil' also needs some backbone—a prosthetic trunk. I'll pound a ten-foot length of rebar into the ground at its back, and then I'll tie the spiral-tied shrub to it every other foot.


'Sky Pencil' will point to the sky.


Here's how to grow 'Gold Cone' juniper.


Here's how to grow 'Sky Pencil' holly.

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