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

Dwarf Palmetto

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Palm fronds:  Not a typical look for any garden in New England.  And a palm growing right in the ground, not just summered outdoors in its container?  Oh yes!

 

Only a few palms can handle an out-and-out Winter, not just the occasional cold snap.  Sabal minor is one.  I've been growing mine in a container for several years; very small individuals don't have the hardiness of larger ones of their species or cultivar. 

 

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This Spring, it gets planted in the garden.  See "How to handle it" below for tactics to get it off to the best possible start.

 

 

Here's how to grow this unusually hardy palm:


Latin name

Sabal minor 'Tulsa'

Common name

Hardy dwarf palmetto

Family

Arecaceae, the Palm family.

What kind of plant is it

Evergreen clumping palm.

Hardiness

Zones 7 - 11

Habit

Clumping and, eventually, suckering.  Trunkless or nearly so. 

Rate of growth

Speed of growth is climate-dependent.  Growth is much slower where Winters test the plant; it's also slowed where Summers remain cool.  See "Culture" and "How to handle it" below.  Fast in milder and warmer climates. 

Size in ten years

In ideal climates—Winters that are only cool but not cold , and Summers that are hot—a clump six to ten feet high and wide.  Much, much smaller in colder climates.

Texture

Iconically tropical; full and dense but, thanks to the sword-like segments on the fan-shaped leaves, not heavy. 

Grown for

its foliage:  It's a palm!  The palmate leaves can be three feet across, on petioles up to five feet long.  Excepting Gunnera manicata, no plant even remotely hardy can say the same.  The leaves are divided into dozens of segments that are sturdy without being stiff.

 

its tolerance:  Sabal minor will grow in just about anything, from poorly-draining clay and hummocks in bogs, to compacted and dry urban planting pockets, to salt-sprayed beachfront sand.  In truly torrid climates it thrives in shade, but it's also comfortable in full sun, especially north of Gulf Coast states.

 

its hardiness: With Rhapidophyllum and Trachycarpus, Sabal is the third genus of the trinity of palms that can be established in Brooklyn and, with luck and uncompromising siting—see "Culture" and "How to handle it" below—up the New England coast to Cape Cod, the Vineyard, and Nantucket.

 

its deer-proof evergreenity:  Palm foliage is maximally evident in the cold months, when deciduous and herbaceous species are just sticks and, respectively, stubs.  All the better that palm foliage is so fibrous that I've never heard anyone complain that it gets browsed.  And all the more reason to grow any palm that's possible in colder climates, where the list of deer-proof evergreens will never be long enough.  Conversely, how unfair that palms are, overwhelmingly, creatures of mild-Winter climates, where there's already an abundance of broadleaves.

Flowering season

Sabal flowers are, as with most palms, numerous without being particularly interesting:  Panicles of small buff-colored things that mature to small fruits about the size of medium olives.  Flowering is rare in colder climates. 

Color combinations

Sabal brings to the garden only green and, via its flowers, buff.  It goes with everything.

Partner plants

With such a strong and distinctive look, but a mid-green coloring, Sabal minor is best when its neighbors celebrate contrasts in texture and form.  Colors that are strongly contrasting—blue, red, pink, rose—are, to my eye, too much fun.  Instead, choose colors that are collateral with green: Yellow and white, tan and copper.  

 

Ferns by definition provide plenty of textural contrast, and those whose foliage is green or yellow-green work better than those whose foliage is bluish or overlaid with purple or silver.  Spreading colonizers would be more interesting than clumpers, whose form would only repeat that of the palm.  The frillier the fronds, the better; simpler fronds, such as those of holly, stag horn, bird's nest or bear's paw ferns, will be too similar to the palm foliage.  Instead, look for choices among such fern genera as Asplenium, Athyrium, Blechnum, Davallia, Nephrolepsis, and Polystichum

 

With foliage that can look as ferny as ferns themselves, conifers are another excellent choice.  I've planted my 'Tulsa' beneath my espaliered Cryptomeria japonica 'Sekkan Sugi'.   

 

Smaller-leaved broadleaves are fool-proof, too, especially if they have round leaves instead of pointed.  Hardy choices include Buxus and Ilex; warm-climate choices include Carissa and Pittosporum, as well as round-leaf succulents such as Crassula and Portulacaria

 

If possible, avoid larger-leaved broadleaves, of which there are so many in mild climates; philodendron, bananas, elephant ears, gingers, ficus, and magnolia are just the beginning.  Planting them near palms usually results in "evergreen overkill."  Indeed, palms are so powerfully evergreen that the bare stems of deciduous neighbors are, for once, a great idea instead of a situation that needs to be finessed.

 

Sword-shaped or grassy leaves are another look to avoid, be they evergreen or deciduous:  Either the segmented palm fronds or the foliage of such neighboring plants will look like an also-ran.  Avoid ornamental grasses, iris and phormium, or nearby aquatics such as rushes, restios, and papyrus.   

Where to use it in your garden

Where Sabal minor is solidly hardy, you can plant it almost anywhere its mounding form would be appealing and functional.  Massed under broad-canopied deciduous shade trees, it would be an ultimate groundcover.  Spaced equidistant in a line—plant twelve or even fifteen feet apart so even old clumps don't meet—it's the ultimate rhythmic mounding down a long driveside bed.  Planted six feet apart, instead, it becomes the ultimate berm-like separator. 

 

Sabal is not a happy container subject for the long term.  Its hardiness is due to naturally deep- and wide-growing roots, as well as a peculiar subterranean trunk (see "Quirks and special cases").  Containers provide neither that roaming-room for the roots nor the extra capacity for the underground trunk.

 

If your Sabal palm is hardy only by dint of being overwintered through the heroic measures suggested in "How to handle it: Another option—or two!," it needs entirely different siting.  Considerations of incrementally-increased hardiness trump off-season aesthetics or even functionality.  If you have a South-facing brick wall, plant the palm three feet in front of it, and work out how to adjust everything else around it.  That said, a palm that each Winter needs to be hay-baled and A-framed is going to suddenly become much bigger and much less attractive—and in a season when it's least possible to screen it, because so much of the surrounding growth will be deciduous.  Even I couldn't face the sight of the palm's Extreme Overwintering every day; thankfully, the garden backed by this South wall of my house is hidden from the rest of the property.  

Culture

Where Sabal is solidly hardy—Zone 8 and warmer—plant almost anywhere, in almost anything.  (That said, growth is fastest in soil rich in organic matter and with ready moisture.)  Fall planting lets the plants get established in the relative cool and moisture of the Winter, so they are ready to revel in the Summer heat without irrigation.  If you plant in Spring, provide sufficient water the first season; thereafter, the plants are self-sufficient in all but the most brutal sun, heat, and drought.

 

In Zone 7, Spring planting is probably advisable, so the plant can become established in preparation for the coming Winter. 

 

At the cold end of Zone 7 and, experimentally, into the warm edge of Zone 6, Spring planting is essential, as is planting only in soils and in situations that ensure excellent Winter drainage. 

How to handle it: The Basics

In Zone 8 and warmer, plant in Spring or Fall.  Water a bit, and, basically, you're done.

 

In colder climates, plant in Spring only.  As is typical for palms, younger and therefore smaller plants don't possess their species' and cultivar's full hardiness.  Buy plants that are growing in three-gallon pots or larger, or grow them up in pots for several years until they're large enough to need a pot of that size.  Pot them in it—and then, the next Spring, consider planting out in your garden.

 

Colder climates, by definition, will have a shorter growing season, with sun that's not as strong, and weather that's much less likely to be sweltering.  On all three counts, these climates are not what a palm prefers: Blazing sun, days in the 90's, and—oh, baby—good growing weather all year round. 

 

So ignore the "it will grow anywhere, in anything" casualness of growing Sabal farther south.  Do whatever you can to make the best of what, for a palm, are your climate's thin and stingy gifts.  Plant in gloriously nutritious soil, if possible on a slight slope so that Winter drainage is impeccable.  Plant close to a south or west-facing wall, preferably one of masonry, which will absorb heat and radiate it back to the palm well into the always (for a palm) chilly nights.  Plant in full sun, if possible; up north, there's so little of it already (for a palm) that you want to let every bit fall on those fronds.  The only exception would be if planting in part shade results in better muffling of Winter wind; see below.   

How to handle it: Another option—or two?

Winter: Palms of any species would prefer to avoid the whole season, although the three genera of hardy palms, Sabal, Rhapidophyllum, and Trachycarpus, tolerate temperatures that fall regularly down into the teens and even, occasionally, into single digits.  Nonetheless, all of these hardy palms thrive into Zone 11—equatorial tropics, where there's almost no temperature difference between Winter and Summer—where they can grow year-round.  Unlike hardier species (fruit trees, say, or peonies) that require Winter weather of such-and-such duration and cold temperatures at least as chilly as this-and-that, even these hardiest of palms only tolerate Winter. 

 

As usual for broadleaved evergreens, a palm must invest a significant amount of energy and structural materials to grow each frond.  It can neither regrow them quickly, especially after months of a rough Winter have trashed them, nor afford to shed them in advance of the rough weather, which hardy deciduous species do so readily.  For a palm, losing a lot of fronds to a bad Winter is, in itself, a true assault.  Keeping a palm alive through the Winter, then, is as much about keeping its fully-fledged fronds alive, i.e., green, as it is about keeping alive the core of the plant: the trunk, the buds of fronds-to-come, and the roots.

 

To help your Sabal survive and (slowly, slowly) thrive, do what you can to mitigate the deadly synergism of Winter's three killing characteristics:  Low temperatures, high wind, and excess moisture. 

 

Although no Sabal will survive in Zone 5, in Zone 6 and above low temperatures per se are the least of your worries.  Thank goodness, because they would be the most difficult to lessen, short of wrapping the palm with heat tape or hundreds of twinkle lights.  Instead, focus on reducing the intensity of wind, and the amount of precipitation and soil moisture. 

 

 

Lessening Winter wind:  Nearby hardy broadleaves and conifers are a big help, especially if one of them can be arching overhead, so the coldest air (always the heaviest) doesn't just slam down onto the plant from open sky.  Having a wall or fence at the back of the palm is a help too, but only if "back" means to the palm's north or east:  You don't want the wall or fence to block the all-important south or west sun, which in your meager climate is weak at best.  

 

In addition, especially in the first few years, consider as many of these Winter tactics as you have room and energy for:  Surround the palm with heavy mulch, then mound up with evergreen boughs as high as you can, even to the point of over-topping the palm.  If you've access to it, surround the palm with hay bales, and fill in around the palm with oak or beech leaves, which don't compact into smothering layers like maple leaves.  Rig up an informal cold-frame by topping the bales with a couple of old storm doors held in place (horizontally) as an A-frame.  Consider loosely tying the fronds together, which could help the plant fit under your A-frame, help one leaf protect the next in terms of wind, and make it easier to surround the base of the palm with mulch and evergreen boughs—although it makes the palm taller overall, so you'll need to mound up evergreen boughs all the higher.  Leave the ends of your A-frame open, or at least open enough that there's still air-flow.  Spray the fronds with anti-dessicant.  Swaddle the palm in wind-baffle fabric, or Reemay, the spun stuff you cover rows of vegetables with, especially if the ends of your A-frame are more open than you'd like.

 

 

Lessening Winter moisture:  At soil level, plant on a slope, no matter how slight.  Wrap the hay bales in plastic so they stay dry (and stay lighter, so are vastly easier to remove in the Spring) instead of soaking up water like a sponge and, in cold weather, acting like a frozen sponge right next to your palm.  An informal A-frame, or even just one panel held lengthwise at an angle, will provide overhead shelter from rain.

Any quirks or special cases?

Sabal palms never form much of a trunk—at least, not above ground.  The trunk, such as it is, forms at ground level or even below ground, which is one reason that these palms are so hardy. 

Downsides

Perhaps not lack of solid hardiness into Zone 6.  If Sabal minor were routinely hardy in Zone 6, establishing it wouldn't be a victory, and encountering it in a garden wouldn't be such a surprise.  Who gets excited about Sabal minor in, say, Georgia, which spans Zones 7, 8, and 9?  Do shoppers there dally while getting out of their cars to marvel that Sabal minor is planted in the parking-lot islands?  I think not.         

Variants

Sabal minor variants are most often chosen for greater hardiness.  Seed from plants that are long-established (and whose hardiness, at least in that location, is therefore well-proven) is collected and germinated, and the next generation is planted, if possible, even farther North.  Colonies in Oklahoma are considered the prime hunting ground.  'McCurtain' originated in McCurtain County, which is at the comparatively mild southeast corner of the state.  Tulsa is about 200 miles farther North, so 'Tulsa' is therefore, conceivably, a bit hardier still. 

Availability

On-line.

Propagation

By seed, although if a Sabal is old enough and happy enough, it can form suckering colonies from which you can (laboriously) harvest well-rooted "pups."  

Native habitat

Sabal minor is native to the southeast United States, from Florida to Texas, southern Virginia to Oklahoma.  Plants of the 'Tulsa' cultivar are from an established colony in Tulsa, Oklahoma.

 
 
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