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: Arborvitae Spirals in Training

 

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Winter is for pruning. Thanks to the new (twelve-foot high!) orchard ladder, the three-ball topiary of hardy orange in the background received its top-to-bottom shaping back in December. Next, the quartet of spirals of gold-leaved arborvitae. They are still young—and short—so pruning them is a matter of kneeling. Thank goodness heavy snows haven't yet arrived. 

 

Because the trunk of each of these spirals is also in training, the first step in the annual grooming is to clip back much of the little tree's side branches—still mostly foliage, really—to expose the developing woody coil. Partly, this helps reveal where the curves were tied in place already, and removing or retying the anchoring lengths of clothesline so as not to pinch the slowly-thickening trunk.

  

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Also, pruning the side growth has direct consequences for the growth that is not pruned—that at the very top of the plant—plus the overall success of forming the spiral and the timeline for its maturation to full height. Shaping the trunk into a spiral inherently means bending it (carefully) to one side, and then around the central tower of rebar. As with training fruit trees, when a woody stem is lowered from vertical (just to a curving diagonal here), side buds become better able to sprout forth. For a fruit tree, that new growth is then more likely to flower and fruit, not just form additional leaves. Arborvitae doesn't produce a showy display of flowers, and the growth on the many side stems that are stimulated by the pruning will be mainly foliar. Even so, the pruning is essential. By being trained into a spiral, the central trunk is kept more-or-less on its side, so it can no longer maintain the dominance it had when vertical. If those new side stems were not cut back, they would each grow vertically in an attempt to become the new central trunk of the arborvitae. A few years without pruning, and these new verticals would have completely surrounded—and hidden and, soon, overtopped—the central spiral.

 

Pruning nips that strategy in the bud, as it were. When cut back by half or more, remaining lateral buds of each of the little side branches are stimulated into growth—as might be still-dormant growth points on the main trunk. This trimming also fully reveals the trunk's developing spiral, which is of course the visual goal of this entire enterprise: A tree that races upward, round and around the central metal core, with just a veneer—or even just a ridge, a "mohawk"—of foliage to enhance the geometry.

 

But such regular and radical pruning also slows down the spiral's overall growth. No surprise, there: Removing the majority of any plant's foliage also temporarily removes the majority of its ability—via the photosynthesis that happens primarily in foliage—to grow. Training arborvitae such that the trunk itself is a spiral, not just the overall mass of clipped foliage around an otherwise straight-and-vertical trunk, is an inherently slow process.

 

These spirals are nearly three feet high. Their training towers are about eight feet high, so these spirals have five feet of height still to achieve. With the training process also reducing the trees' ability to grow, the annual increase in new stem at the top of each spiral might just be six inches. Even if that six inches were all vertical, it would still take a decade to achieve that five feet.

 

But the trunk is bring grown as a spiral, so the actual increase in height from that six inches is just a couple of inches at best. Forming an arborvitae into such a "trunkal" spiral, then, is not a project of years or even a decade but, rather, one of a generation, a lifetime. 

 

Here's how to grow this colorful and hardy conifer.

 
 
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