Philadelphia and the poinsettia go back almost 200 years, but the relationship has never been exclusive. It involves a raft of iconic names and institutions in this city's lengthy horticultural history: Bartram's Garden, Col. Robert Carr, Robert Buist Sr., J. Liddon Pennock Jr., and the Pennsylvania Horticultural Society.

PHS has mounted a small exhibition showcasing the popular "Christmas plant," in all its local connectivity, through Dec. 19 in the society's newly refurbished library.

As early as the 14th century, the beautiful native Central American plant we know as poinsettia was called a tongue-twisting cuetlaxochitle by the Aztecs. The showy, red "flowers" - technically, modified leaves, or bracts - were also used to make a reddish-purple dye; the plant's milky sap was said to reduce fever.

In the 16th and 17th centuries, these winter-blooming perennials in the euphorbia or spurge plant family were commonly used in Christmas rituals in Mexico.

Which is where, in 1828, they caught the eye of Joel Roberts Poinsett, for whom they later would be known.

A prominent South Carolina politician with a botanical bent, Poinsett was the first U.S. minister to newly independent Mexico. He began collecting cuttings and sending them to friends, including those at Bartram's Garden, the famous commercial nursery founded by John Bartram in 1728 on the banks of the Schuylkill.

By then, the business had been passed down to Ann Bartram Carr, John's granddaughter, and her husband, Col. Robert Carr, who were largely focused on international trade in native North American plants. Carr introduced the poinsettia into commerce on June 6, 1829, at an "exhibition of fruits, flowers and plants."

The first public flower show of the fledgling Pennsylvania Horticultural Society, it was held before hundreds of people at a now long-gone Masonic Hall on Chestnut Street. And it was remarked upon in windy detail in the Philadelphia National Gazette.

"Among the foremost candidates for admiration," the scribe scribbled, were the magnolias, pelargoniums, peonies from China, Arabian coffee tree, West Indian sugar cane . . . and, by way of Bartram's, "the new Euphorbia."

"People had never seen anything like it. It attracted a lot of attention," said Janet Evans, senior manager of PHS' McLean Library, who coordinated the current exhibit.

Five years later, Robert Buist Sr., a Scottish-born nurseryman and longtime PHS officer and exhibitor, took the plant to Europe, where its botanical name became Euphorbia pulcherrima.

Translation: "the most beautiful Euphorbia."

The poinsettia may have debuted in the United States as a novelty, but it slowly became more available.

In 1860, Thomas Meehan, a British-born plantsman who ran a nursery in Germantown, wrote in his Gardener's Monthly, the poinsettia "sells quite well."

Buyers, Evans says, were "regular middle-class gardeners who place plants on their windowsill or in greenhouses, if they had them."

From 1900 through the 1990s, poinsettias basically went viral, thanks to the Ecke family of Encinitas, Calif., whose secret grafting technique produced lush, compact plants, most unlike the weedy Mexican variety that grew 10 to 15 feet tall.

The Eckes bred fantastic colors, leaf shapes, and sizes. And they marketed like mad, supplying free plants to popular TV shows and the "women's magazines," whose poinsettia-filled photo shoots reinforced its reputation as "the Christmas plant."

J. Liddon Pennock Jr., the Philadelphia society florist known as "Mr. Flower Show," did his part, too. From 1971 to 1973, he filled Richard M. Nixon-era White House at Christmastime with Ecke poinsettias.

In the 1990s, the poinsettia story took a dramatic turn.

Around 1996, university researchers independently replicated and published what Evans calls the "secret sauce," the Eckes' closely held - and unpatented - grafting method, which had revolutionized the poinsettia trade and given them a near-monopoly.

Then, in 2012, Paul Ecke 3d sold to the Dutch-based Agribio Group, one of the world's largest plant breeders, producers, and distributors. The Ecke name remains on the poinsettias, which still account for 70 percent of domestic market share, and half of international.

But the three-generation, century-old, American family business is no more.

We pause for National Poinsettia Day, created in 2002 in honor of Poinsett, who died on this day in 1851. Note, however, that while U.S. fans of "the Christmas plant" may celebrate his legacy, Mexicans, apparently, do not.

Chronica Horticulturae, the journal of the International Society for Horticultural Science, reported in a 2011 paper that Mexicans coined their own word to memorialize him - and it wasn't poinsettia.

Poinsettismo: It means arrogance and high-handedness.

EXHIBITION

"The Poinsettia Story" exhibition runs through Dec. 19 at the Pennsylvania Horticultural Society's McLean Library, 100 N. 20th St., first floor.

Library hours: Monday-Friday, 9:30 a.m. to 5 p.m.

The exhibition will close at 3 p.m. on the last day.

Information: 215-988-8800 or phsonline.org.EndText

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