U.S. Botanic Garden Presents DC Landmarks Made From Plants

U.S. Capitol made from plant-based materials at the U.S. Botanic Garden's annual holiday display

Plant-based replica of the United States Capitol

Those of us who live near Washington, DC seldom fail to be moved by the majestic buildings and monuments that comprise our capital city. And the United States Botanic Garden, one of the oldest botanic gardens in North America, is one of them. Now at holiday time comes a special treat: the Garden’s annual tribute to the city’s most famous landmarks constructed from, you guessed it, plants and other plant-based materials.

The eye-catching display is part of the U.S. Botanic Garden’s “Season’s Greenings” holiday exhibit that also features seasonal flowers and shrubs, a garden railway with model trains and a top-notch collection of unusual poinsettias. It was created by Paul Busse (most famous for the New York Botanical Garden’s Holiday Train Show) and his Kentucky-based firm, Applied Imagination. A team of horticulturalists, botanical architects and landscape designers used over 70 different plant materials to build their sculptures.

img_2349

Model train passes through a botanical Grand Canyon

Botanical Landmarks On A Mini Mall

At the heart of any trip to Washington, DC is a trip to the National Mall. And the botanical replicas, positioned as they are along the broad walkways and twin pools of the Garden Court, echo the actual ones just a stone’s throw away outside. Each architectural gem is sited high on a mound from which it surveys its own pint-sized garden vista.

The crown jewel of the collection, the U.S. Capitol, is located to the left of the Court.The seven-foot-long structure, which is formed of sycamore leaves, willow sticks, acorns and other natural materials, took over 600 hours to complete. A peek inside reveals the Statue of Freedom and other figures fashioned from beech nuts, corn husks, acorns and pinecone scales.

img_2331

U.S. Capitol

Facing the U.S. Capitol on the opposite side of the Garden Court is the Washington Monument constructed from sycamore leaves, sea grape leaves and moss. The Garden’s blue-tiled ornamental pool (one of a pair) stretches behind it.

img_2313

Washington Monument

A gourd forms the dome of the Jefferson Memorial. While inside presides a mini President Jefferson with hair made out of lichens.

img_2321

Jefferson Memorial

Occupying the far end of the pool from the Washington Monument, the Lincoln Memorial features an exterior of sea grape leaves and architectural details made from kangaroo pods, sisal rope and grape tendrils among other materials.

img_2328

The Library of Congress shines amidst its lush green landscape. Its facade is crafted from elm and locust bark. Sea grape leaves make up the terrace.

img_2332

Library of Congress

The U.S. Botanic Garden conservatory has a facade made from horse chestnut bark and willow sticks.

img_2316

U.S. Botanic Garden

Located on the opposite side of the pool from the U.S. Capitol, the Supreme Court building features a frieze made from beech nuts, acorns and silver birch buds.

img_2340

U.S. Supreme Court

The White House is surrounded by a fence made from screw pod rails and cinnamon tops. while bas-relief columns in palm frond stems and cinnamon curls. There’s a swing-set in front.

img_2329

For more information on this fun exhibit as well as the garden railway (which run through January 3, 2017), click here for the official U.S. Botanic Garden website. It’s entirely worth the visit.

 

New Hybrids Promise To Rock Your Poinsettia World

img_2386-1

The little yellow buds in the center of the poinsettia are the actual flowers.

Today, December 12, is National Poinsettia Day; a day set aside to honor the plant that has become a symbol of the American holiday tradition. And while not everyone’s a fan, it’s hard not to marvel at the species’ growing popularity. Poinsettias have come a long way since they were first introduced to the United States by Joel Roberts Poinsett. In his day, they were remarkable for their brilliant red color. These days, they come in every shade of white, pink and orange and even blue.

220px-JRP-SoW,_S

Joel Roberts Poinsett

About poinsettias 

While they’re now commonplace in the United States, poinsettias (Euphorbia pulcherrima) are actually native to Mexico where they grow wild in the mountain forests of the Pacific slope. In their natural habitat, poinsettias are sprawling and vine-like, often taking the form of shrubs or small trees.

WIld poinsettia/pinterest.com

Wild poinsettia/pinterest.com

Owing to their brilliant red color, poinsettias have been a part of Christmas in Mexico since the mid 1600’s. But they were virtually unheard of in the United States until the early 1800’s. This is when Poinsett, who was the United States’ first ambassador to Mexico and an amateur botanist, happened upon some while stationed in the tropical country.

Poinsett was so fascinated by the unusual-looking species that he began sending stems back to his family in South Carolina. When he later returned to his native State, Poinsett started propagating his own plants from stem cuttings, which he then introduced to botanical gardens and nurseries throughout America.

img_2382

Euphorbia pulcherrima ‘Orange Spice’

As it grew in popularity owing mainly to efforts by Poinsett, the poinsettia became known in the United States as the ‘Mexican Fire Plant.’ The plant’s scarlet, star-shaped leaves and winter-blooming properties made it a colorful addition to holiday households. Following Poinsett’s death, the plant was renamed Poinsettia in honor of its discoverer.

 

The Ecke Family

The poinsettia industry really took off in the early 1900’s when a German immigrant named Albert Ecke started selling plants from a street stand on Sunset Boulevard in California. Given that the poinsettia was one of only a handful of plants known to bloom in the winter, Ecke soon convinced area growers of the advantages of propagating the plant to raise cash during the off-season.

When Albert’s son, Paul Ecke Jr. took over the business in the 1960’s, he began an intense marketing campaign, sending fresh plants to TV stations at Christmas and making personal appearances to promote the plant’s many benefits. His efforts landed the poinsettia in many popular women’s magazines and vastly increased the poinsettia’s overall visibility.

poinsettia

During the same period, Ecke Sr. came up with a technique that greatly improved the appearance of the often spindly-looking plant. By grafting two varieties of poinsettias together, he was able to create a fuller, more compact plant with many more blooms; a precursor to the specimens we purchase today. Until the technique was finally revealed, the Eckes maintained a 90 % share of the American poinsettia market.

Ecke family/Ecke Ranch

Ecke family/Ecke Ranch

 

The leaf is the flower

Poinsettias’ bright red leaves are often mistaken for flowers when in fact they are bracts. The plant’s actual flowers are the tiny cluster of yellow orbs in the poinsettia’s center. In order to produce the colored bracts, poinsettias require a daily regimen of at least 12 hours of darkness followed by bright sun (a long process undertaken by the grower.)

Although the plant originated as a red-leaved species, you can now find poinsettias in every shade of salmon, pink, creamy yellow and white. Modern hybrids, created by a cross between the traditional Euphorbia pulcherrima and Euphorbia cornastra, include varieties with reduced central flowers. Still other varieties are marbled or striped.

(All photos taken at the United States Botanic Garden holiday exhibition.)

img_2386

Euphorbia pulcherrima ‘Autumn Leaves 2016’

img_2374

Euphorbia pulcherrima ‘Jingle Bells’

poinsettia white

Euphorbia hybrid ‘Princettia Hot Pink’

img_2376

Euphorbia hybrid ‘Princettia Max White’

img_2394

Euphorbia hybrid ‘Luv U Pink’

img_2379jingle-bell-rock

Euphorbia pulcherrima ‘Jingle Bell Rock’

 

How to pick a poinsettia

When shopping for a poinsettia, make sure to look for a plant that has dark green foliage all the way down to the soil line. Choose plants that have fully-colored bracts and no green around the bract edges. Greened edges are a sign that the plant is older and won’t last as long. Never buy plants with yellowed leaves, which are sure signs of plant stress.

 

poinsettia in foil

Although bred to be compact, poinsettia branches break easily. Check to make sure no cracked branches are being held up by the foil sleeve. And always remove the sleeve after purchasing. Poinsettias need plenty of air circulation to survive.

Water well and allow the plant to dry out before re-watering. Avoid fertilizer, which will hasten the decline of the colored bracts. Expose the poinsettia to plenty of sunlight to keep its bright color.

Toxicity

Although the sap and latex of the poinsettia leaves can cause a mild allergic reaction in some sensitive individuals, the plants themselves are not poisonous. As for the commonly-held belief that the plants are toxic to pets, the Pet Poison Helpline confirms that while poinsettias are listed as toxic to dogs and cats, they are only mildly irritating to the mouth and stomach if swallowed.

 

Fun fact

Poinsettia is traditionally capitalized since it is named after a person. According to the Oxford Dictionary, it is pronounced poin-set-ee-ah.

 

 

 

New Study Reveals Ants Know How To Grow Plants

fiji-ant

“Even the sharpest ear cannot hear an ant singing” -Sudanese Proverb

(Red ant on Fijian palm leaf)

Just when you thought you’d heard it all, this week comes the revelation that a certain species of Fijiian ants has been growing plants for millennia.  And they’ve been doing so for far longer than humans. The ants have been growing crops and establishing their colonies within them all while tending their own teeny tiny community gardens.

Researchers from the University of Munich in Germany made the surprising discovery while studying a species of ants called Philidris nagasau. The ants, which are indigenous to Fiji, establish their colonies high in trees on the tropical islands. While observing the ants’ behavior, the scientists discovered that the insects had formed specialized communities devoted entirely to gardening. And they were growing fruit.

fijian-forest

Tropical forest in Fiji

While the earliest known human farming dates back roughly 23,000 years, DNA evidence suggests that Philidris nagasau may have been growing plants as far back as 3 million years. And not only have they been growing fruit, they’ve been cultivating six different species of the same plant known as squamellaria. Squamellaria is a genus of flowering plants in the Rubiaceae family (that includes the coffee plant among others.) It is endemic to the islands of Fiji.

squamellaria-in-macaranga-tree

Squamelleria fruit in macaranga tree

Although many epiphytic plants (plants that grow harmlessly on other plants) have teamed up with ants before to gain nutrients, this is the first instance of a single species of ants actively engaged in planting and fertilizing the seeds of a plant.

How they garden

ant

“The ant’s a centaur in his dragon world.” – Ezra Pound

It turns out that the Fijiian ants are involved in every aspect of gardening, from planting to harvesting, which has a direct impact on their housing and social behavior. The process begins even before the squamelleria are ripe, when the ants start gathering the fruits’ seeds and sowing them in elbows and cracks of the host tree’s branches. As the seeds germinate, the ants stand guard over the tiny sprouts, while fertilizing them with their feces.

ant-drawing

Once the squamelleria begin to mature, they swell into soft, bulbous structures composed of many chambers called domatia. The domatia serve as the ants’ home once they’re large enough for the mini gardeners to enter. As the fruits expand in size, the chambers do, too, and more and more fertilizer-producing ants move in, thus establishing a relationship that is beneficial to both parties.

The ants live inside the domatium during the life of the squamelleria where they form ever expanding colonies. Once the fruit appears, the ants eat the sugary flesh, collect the seeds and repeat the cycle.

According to the researchers, each ant colony farms dozens of fruit plants at the same time, while producing a system of mini highways that link one to another. The entire connected network of community ant farms often encompasses many trees.

palms

Researchers have never encountered these ants living anywhere other than in these fruits nor the plants living without the ants. Neither species can survive without the other.

The study was led by Professor Susanne Renner and Guillaume Chomick and published in the journal Nature Plants.

 

How To Protect Your Evergreens From Winter Damage

cover

You could say that evergreens are the stars of cold weather, infusing color, texture and form into drab winter landscapes. When well sited, watered and fed, most can stand up to the harshest of conditions. Still, some evergreens are less equipped than others to battle cold, winds and exposure to bright winter sun. These are the plants that benefit from a little extra TLC to help prepare them for colder temperatures.

Without proper preparation, cold weather can spell disaster for some evergreens. Here are steps you can take now to prepare your most vulnerable plants for winter. HINT: The most important step is to water.

 

WATER YOUR PLANTS

The most important thing you can do to prepare your evergreen shrubs and trees for winter is to water them. And that means making sure they’re well hydrated beginning in early fall, a time when many people stop watering.

Rainfall can help with the job, but if you experience a dry spell it’s important to water your evergreens and continue to do so regularly until the soil freezes. Plants will hold on to the water and use it throughout the winter.

watering-an

The most important thing you can do for your evergreens is to water them

Watering is crucial because all evergreens, and especially broadleaf varieties like rhododendrons and hollies, lose moisture from their foliage in a process called transpiration. Once the ground has frozen, it deprives plants of water, making it impossible for them to replace what is evaporating. This can lead to a common type of winter injury called desiccation, also known as ‘winter burn.’

evergreen.frozen yew

Signs of desiccation can begin appearing as early as mid winter, when leaves of a plant may turn brown at the tips or several branches start to dry out or die. (This kind of damage typically shows up on the side of the plant that faces into the wind or has a southwestern exposure.) Other plants will hold on to their green color until spring or early summer when they begin to push new growth. Then their leaves will suddenly turn brown, start to curl and fall off.

TO DO:   “Winterize” your evergreens by deep watering, which promotes deep rooting of plants and shrubs. Water them every other week, making sure the soil is moist to a depth of between 12 to 18 inches. Do this until the ground freezes.

 

PROTECT WITH SPRAY

Evergreens that are prone to desiccation, especially the broad-leaved varieties, often benefit from a little help in the form of spray. Anti-transpirant (or anti-desiccant) sprays, readily available at nursery and hardware stores, can protect tender leaves and stems by reducing water loss during times of plant stress.

www.wilt-pruf.com

www.wilt-pruf.com

Sprays provide a protective, film-forming coating that slows down moisture loss and protects plants from drying out. The transparent layers wear off gradually without interfering with plant growth or respiration.

In the winter, most sprays can remain effective for up to four months. Proper timing is key: it’s best to spray your plants in the morning when temperatures are above 50 degrees so the product has time to dry. You’ll need to reapply the spray once or twice during the winter.

(By the way, the sprays work great on indoor holiday greenery, too.)

TO DO: Spray plants once in December and again in February to prevent water loss and protect their leaves.

 

BUILD A SCREEN OR SHELTER

Shelters and screens are great for smaller shrubs that you’d like to protect from excessive wind, falling snow and road salt damage. Although you can buy ready-made frames at the store, burlap, some lumber and a few stakes are really all you need to make one on your own. Steer away from plastic, though. You could cook your plants.

How to at hgtvgardens

How to at hgtvgardens.com

To make a screen, drive the stakes into the ground on the windward side of the plant or on its southern exposure, where it is at greater risk of exposure to swings in temperature. Staple the burlap to the stakes.

To make a shelter, place stakes all around the plant to form an A-frame. Stretch the burlap across the structure. Or, you can attach plywood panels to the stakes to create an even sturdier frame.

TO DO: Take an inventory of your landscape and pinpoint any plants that may be vulnerable to winter stress. Evergreens that face the wind or have a southern exposure may need screens to guard against winter burn. Pay particular attention to plants that are located under the roof line, where falling snow could be a hazard. A-frame shelters are great at shedding heavy snow and ice. For a great tutorial on how to build screens and shelters, go to thisoldhouse.com.

 

TIE THEM UP

How to at gardeners.com

How to at gardeners.com

Evergreens can be damaged by heavy snows or ice storms that snap their branches. Foundation plantings can be particularly vulnerable, since they are often exposed to snow falling from the roof. A good way to protect your plants is to tie them up to give them a little extra support.

Using heavy twine or string (I use green-colored twine so it doesn’t show), begin by attaching the twine to the base of the plant and wind the plant up, drawing in clumps of branches as you go. Once you end up with a tight spiral, you can leave it alone or cover the shrub with burlap.

TO DO: Tie up foundation plantings like boxwood and azaleas to prevent against breakage and dust snow off of fragile bushes with a broom or by shaking to make sure it doesn’t accumulate.

 

MULCH

mulchMulching in the fall is a great way to protect your evergreens from fluctuations in soil temperature and damaging moisture loss. Mulches are proven water conservers; able to reduce moisture loss anywhere from 10 to 50 percent. Adding a protective layer of mulch insulates your plant and prevents water from from escaping from the subsoil.

TO DO:  Depending on how big the root zone is, make a 3- to 6- foot diameter circle around the shrub or tree and apply a 2- to 3-inch layer of mulch, making sure to mix in some organic materials to add nutrients to the soil.

A word of caution: don’t pile the mulch up around the plant crown or tree trunk. This could cause the plant to rot and die. A distance of six inches or more is a good rule of thumb to follow.

 

Last word

Even if your evergreen looks bad, try to refrain from pruning brown foliage or branches until after the winter. Wait until the spring or you risk further damaging the plant.

 

Why Leaves Change Color and Other Fun Fall Facts

shutterstock_85888030

Autumn is a second spring when every leaf is a flower.

-Albert Camus

Camus has a point. I like to think of fall from an Alice In Wonderland perspective; that is, autumn is a time when we shrink in proportion to our gardens while, untended, the leaves ‘bloom’ above us.  And each year, nature provides new surprises, awing us with colors so vivid and color combinations so daring as to leave little doubt as to her power to create designs so far superior to our own.

While it’s generally believed that cold weather brings on the change in the leaves’ color, the process is in reality a bit more complex. Yes, temperature and weather can affect the intensity and duration of color, but the real reason for the change lies in the growth process of the tree itself. And just like flowers in the garden, each tree species has its own colors and ‘bloom’ period that corresponds with the closing of each growing season.

autumn-landscape

Nature’s garden

Why do leaves change color?

Leaves change color due to the process of photosynthesis. During the growing season, leaves act as food factories for the plant, capturing sunlight to turn carbon dioxide and water into oxygen and sugar. A chemical called chlorophyll, which absorbs light energy, is responsible for making this happen. It is also the reason why most leaves are green.

In fall, however, as temperatures drop and the days get shorter, the leaves stop their food making process. As the chlorophyll naturally breaks down, the green color disappears from the leaf and yellow and orange pigments become visible. Although unseen until now, the colors yellow and orange are present in the leaf throughout the growing season.

sassafras

Orange-yellow sassafras leaves on Maryland’s Eastern Shore

Still other chemical changes during this shut-down stage result in altogether new pigments being developed such as the colors red and purple. These colors emerge as a result of varying amounts of sugars that are trapped in the leaves after photosynthesis shuts down.

red-maple-tree

Maple tree in fall

As fall progresses, the cells near the juncture of the leaf and stem weaken and the leaves begin to fall from the tree. The additional pigments begin to break down and the only color left is brown. Some plants, though, (like oaks) retain their brown foliage for a good part of the winter.

img_2251

Sycamore leaves turn shades of brown

Weather has a big effect on color

Weather conditions can affect the leaves’ color and duration and are the reason why each year the landscape looks slightly different. These conditions include temperature, amount of sunlight and available water supply.

Lots of sunlight combined with low temperatures, for instance, produces brighter reds but shortens their duration. An early frost, however, spells the end of the show. And drought stress during the summer can result in early dropping of leaves before they have a chance to form any color at all.

sugar-maple

Sugar maple leaf in process of changing color

Surprisingly, a combination of rain and overcast days tend to increase color intensity.

yellow-orange-leaf

 

While the best and brightest show usually follows a growing season with ample amounts of water followed by a dry spell.

sugar-maple-image

 

The ‘Roomba’ of Gardening: A Robot That Weeds

fr-header-bg-1024x645

Franklin Robotics ‘Tertill’ promises to weed your garden for you

Last year was a particularly big one for weeds, with many of us struggling in vain to control them in our gardens. But thankfully, just in time for next summer, there’s an invention that just might alleviate this tiresome chore. It’s called Tertill and it proposes to do the weeding for you. Continue reading

Ten Really Great (Almost) Black Flowers To Plant In Your Garden

black-bat-cover-again

Black bat flower

In painting, black is the darkest hue, achieved by bringing any color to its darkest value. Black gives structure to a composition, creating the illusion of depth by drawing the eye. And in the garden, black (or almost black) flowers perform the same function, placing other colors in dramatic contrast while adding volume to the composition. I’m already planning gardens for my clients for next spring. And, included in many are a whole host of these elegant, almost-black plants and flowers. Continue reading

Ten Minor Bulbs to Plant Now for A Big Bang In the Spring

shutterstock_152262311 (1)

Winter aconites blooming in the snow

One of my favorite places to visit in the early spring is Delaware’s historic Winterthur Gardens. The estate’s stunning 60-acre naturalistic garden has one of the finest displays of early spring bulbs around, all staged to flower successively in a colorful quilt woven of purples, pinks, blues, yellows and whites. And every year when the show begins on the garden’s famous March Bank, I vow that I will plant hundreds of these tiny bulbs the coming fall so that I, too, can bask in their miniature early-spring glory. Continue reading

Is the Self-Healing House the Garden of the Future?

screen-shot-2016-10-16-at-12-25-16-pm

Image via Edwin Indira Waskita

There’s a fascinating image that has stuck with me ever since, years ago, I read the sci-fi novel Goodbye and Thanks For All the Fish (the fourth installation in the series the Hitchhiker’s Guide to the Galaxy.) In the novel, author Douglas Adams describes a four-walled house turned inside out. If you entered the house, you found yourself ‘outside’ in a green space, complete with lawn, benches and walking paths. If you exited the house, you found yourself ‘inside’ in a far less desirable place Adams termed the Asylum. Continue reading