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

Red Shield

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This is one the best purple-foliaged plants in the garden.  Each year, it looks the most amazing the week before hard frost will kill it.  Sigh. 

 

Red Shield is a tropical hibiscus.  It's not purple because it's a new and sophisticated hybrid.  Red Shield is the species itself, Hibiscus acetosella, not a cultivar name.  Its sophistication is natural, indigenous, and innate.  Cool, eh?

 

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The shiny purple leaves seem to be channeling either a decent Japanese maple or a remarkable new kind of pot.  Actually, they're edible, if not smokable.  They look and taste delicious frollicking with lettuce leaves.

 

Thanks to their heat-proof color, they look just as smashing in the garden.  Burgundy goes with every other color you could ever need.  I cozy Red Shield up to different colors each year just to put its cosmopolitan ease to the test.  This year, one of the near neighbors was Bulbine frutescens 'Hallmark'.   

 

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Purple leaves right by grassy foliage and yellow-and-orange flowers?  Looks good to me.  And next to both, the blue-green trunk of the Chinese parasol tree, Firmiana simplex

 

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That looks good, too.

 

The hibiscuses start in May as rooted cuttings from a local nursery.  A foot tall at best.  By September, though...

 

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...they're five-foot bushes in five-gallon pots.  That's Ilex cornuta 'O'Spring' in a pot at the front.  Of course, Red Shield looks great with it, too.

 

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By late October, the Red Shield is a foot taller still.  Would it be kissing the bottom leaves of the Firmiana by December?  We'll never know.  Firmiana just misses being hardy in Rhode Island—but please to visit the happy specimen in the video, in Tompkins Square Park in Manhattan—so by December, mine is safe and dormant in my basement. 

 

This year I'll bring my quartet of Red Shields into the greenhouse for the Winter.  Maybe they can live on for years, becoming more purple and more cosmopolitan all the while.

 

 

Here's how to grow this fail-safe annual:

 

Latin Name

Hibiscus acetosella

Common Name

Red Shield

Family

Malvaceae, the Hibiscus family.

What kind of plant is it

Evergreen shrub.

Hardiness

Zones 9b - 11

Habit

Upright as well as branching from the base; the branches are upright as well. 

Rate of Growth

Very fast.

Size in six months

A shrub six to eight feet tall and five feet wide.  Even as an annual in cooler climates, H. acetosella can be expected to get three to four feet tall if it's not pinched.

Texture

Lacy and intricate:  The leaves have five lobes, and they're as notched and pointy as those of Japanese maples.  Their deep burgundy color is absolutely reliable even through the hottest weather, and only enhances the resemblance.  Unless pinched to force denser growth and restrain height, the plant is open enough that it can be grown even at the front of a bed.   

Grown for

its colorful as well as heat-proof foliage:  See "Texture" above.  The leaves are also edible, so add them to salads.  You'll probably want to pinch this plant once, twice, or even more often, so you'll have plenty.  See "How to Handle It" below.

 

its self-reliant height:  As an annual, H. acetosella rarely needs any support, and brings the woody presence of a shrub to what might otherwise look like (and be) ephemeral and delicate stretches of warm-weather foliage and flowers.  Where it's hardy in-ground, though, it eventually leans and even flops, as usual in the way of leaning and flopping, just about the time (in this case, Fall through Winter) it buds and bloom.

 

its vigor and toughness: H. acetosella laughs at any Northerner's definition of scorching heat and pitiless drought.  In my experience, the foliage doesn't scorch even if the plant is astoundingly pot-bound in a container sitting in blazing sun on pavement so hot you can't walk on it barefoot.  Even starter plants set out in May will have become six-foot monsters by early October.   

Flowering season

Late Fall through Winter:  Hibiscus acetosella needs shorter days to become inspired to form buds.  Its cranberry-pink flowers are showy, but not moreso than the foliage.  It will bloom all Fall and Winter, only stopping when the days have lengthened again in Spring.

Culture

Full sun, almost any soil, average water.  Hibiscus acetosella is the epitome of easy.

How to handle it

Combine Hibiscus acetosella's quick growth, colorful and gracefully-textured foliage with its immunity to high heat, strong sun, and occasional drought, and you have a plant that should be welcomed into almost any warm-weather garden.  

 

Its vertical but open shrubbiness provides bright and easy height, and it's just as happy in large containers as in-ground.  Unlike so many other large-growing annuals, Hibiscus acetosella doesn't give up on its lower foliage by mid-Summer; it stays colorful and attractive.  You can plant Red Shield where it will be seen from head to toe.

 

Pinch young plants at planting, or even cut them back by half.  Pinch once more in a month.  If you're looking for the tall and open look, then let the stems grow on their own.  The stems aren't graceful if allowed to grow for several feet only to be pinched yet again, so don't think it's OK to forget to pinch in July but resume in August.  Like Forsythia, this plant can be ruined by being given a haircut.  Pinch early and often and then, either then let the plant grow on its own, or prune the stems all the way back to within inches of where you last pinched them. 

 

Plants can sometimes be floppy right from the ground: Their roots just don't hold the entire bush as upright as you'd like.  A thick and short stake just to secure the largest stem at its base can give the whole bush the support it needs without sacrificing the free sway of the upward stems.  In this regard, Hibiscus acetosella is similar to another warm-weather giant, Lion's Ears, Leonotis nepitifolia

 

If dense and bushy is the goal—or if you just get into pinching, or you really enjoy eating the young leaves in salad—pinch away, week by week by week.  You'll produce a rounded and dense bush, and also avoid the need to stake.

 

The burgundy foliage goes with anything and everything, from pink to yellow to red to blue to white, so Hibiscus acetosella is an asset to all color schemes.  Its Japanese-maple-like foliage would be particularly highlighted by large-leaved partners, and the deep burgundy would really smolder if there were bright flowers or colorful foliage nearby, too.  Maybe you can achieve both goals independently, with a variegated grass to one side and huge-leaved (and sun-tolerant) hostas to the other?  If you garden in Zone 7, though, you could pair with a variegated Clerodendron trichotomum 'Harlequin', whose heart-shaped leaves are vividly partitioned in yellow, white, and green.  I keep one in a pot: Maybe it will sit by the Hibiscus next Summer.

 

I'm overwintering my quartet of potted Hibiscus acetosella, but not because I'm interested in the flowers.  They'd only appear during the Fall and Winter, when the plant is in the greenhouse.  No, I'm overwintering my Red Shields to see if the plants can be trained into standards.  Then I can have the height as well as the dense foliage—not to mention all those pinched-off leaves for salads.

Downsides

As a warm-weather annual, Hibiscus acetosella is non-blooming, pest-free, and deer-proof.  Where it's hardy in-ground, though, it can self-seed profusely.

Variants

Despite all the common names you'll see at nurseries and on-line—Panama Red, Maple Sugar, Cranberry Shield, African Rosemallow, Red Hibiscus, False Roselle—there's only one actual cultivar, 'Haight Ashberry', which has variegated leaves that, to my eye, only lessen the impact of the pure-burgundy foliage of the species itself.  

 

False Roselle, however, correctly implies that there's a "true" roselle, which is H. sabdariffa.  It has simpler green leaves (but showy purple stems) and is the source of the "hibiscus blossom" ingredient in tea.  The flowers themselves aren't much, but the buds are bright burgundy.  The flowers mature to shiny and showy burgundy pod-fruit-flower like complexities (actually, it's the calyx that's providing most of the show) used world-wide in warm-climate cuisine for tea and jam.  Roselle can be grown as an annual, and I'm looking forward to trying it.  

Availability

On-line and at nurseries.

Propagation

By seeds as well as by cuttings, which Kathy Tracey at Avant Gardens assured me root even in water. 

Native habitat

Hibiscus acetosella is native to Africa.  

 
 
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