Читать книгу An Abundance of Flowers - Judith M. Taylor - Страница 12

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Poinsettia

WHEN THIS project began, I asked a distinguished horticultural editor if he would like an article on the development of the poinsettia. Until then he had put up with my peculiarities and indulged me, but here he drew the line. “Poinsettias,” he said firmly, “are not plants any longer, they are a commodity.” He truly believed what he said, but oh, how unfair.

The beautiful poinsettia, known for its scarlet bracts, comes to us encrusted with myth and legend, as befits a royal plant of the Aztecs. The Nahua people in Mexico called it cuetlaxochitl (xochitl is the ancient Nahuatl word for an ornamental flower). Poinsettia is a desert plant and very sensitive to the cold. As Tenochtitlan (now Mexico City) was at high altitude, poinsettia did not flourish there, but every winter the rulers imported thousands of the plants from warmer regions. Extracts of the plant were used to dye cloth, and its latex was used for medicinal purposes. The Spanish conquerors and missionaries attempted to erase all evidence of the preceding pagan Aztec religion, but records have survived showing that the plants were used for religious ceremonies in the winter.

Once the Spanish friars took over, they adopted the brilliant red plant as part of the Christmas ritual, and the Spanish-speaking Mexicans named it flore de nochebuena, the flower of the Holy Night (Christmas Eve). The vivid red bracts of poinsettia, which emerge in early winter, have signified the festive mood at Christmas and the joy of the season for over 150 years in the United States and Europe. In what follows, I hope to establish the actual story of its arrival in the United States and Europe and its extraordinary development, and will attempt to clear away all the accumulated misinformation and cobwebs.

BOTANY

The poinsettia (Euphorbia pulcherrima Willd. ex Klotzsch) is a member of the large and diverse family Euphorbiaceae. The plant originated in southern Mexico and northern Guatemala. In its native habitat, this species is a winter-flowering shrub that grows over three meters high and is a common landscape plant. The sap is milky and may produce dermatitis in susceptible individuals. The umbel-like cymes are subtended by many showy bracts, usually red, but breeders have used their imagination to produce many different colors, including white, pink, and purple. In part this has been driven by the demands of the market.

Other major innovations in the poinsettia resulted from the remarkable discovery by Gregor Gutbier, an Austrian poinsettia breeder in the 1980s, that grafting poorly branched plants onto well-branched plants increased branching in the propagules of the restricted-branching plant. This effect was demonstrated to be due to the transmission of a phytoplasma from an infected to a healthy plant. The phytoplasma was later shown to be similar to the infectious agent causing peach X-disease and spirea stunt but acted in a benign manner in poinsettia. Once the role of the virus was recognized, it became standard procedure to introduce the beneficial pathogen to new poinsettia seedlings by grafting. Propagules from grafted plants kept their free-branching trait. Other innovations in poinsettia production include pinching to increase branching, and the use of growth regulators to reduce plant size.

Species euphorbias in their native habitat. Artist unknown.

Reproduced by permission of Chronica Horticulturae

Joel Roberts Poinsett. Artist: Charles Fenderich (1838).

Reproduced by permission of National Portrait Gallery, Smithsonian Institution

JOEL ROBERTS POINSETT AND THE POINSETTIA PLANT

The common name, poinsettia, honors an American, Joel Roberts Poinsett (1779–1851), who saw the plant in southern Mexico in 1828. For years it has been assumed that Poinsett came across the gorgeous plant in Taxco in southern Mexico, and took it home to Charleston, South Carolina, in 1828. That is not correct.

From there he is said to have sent cuttings to Colonel Robert Carr, a nurseryman in Philadelphia, Pennsylvania, whose wife, Ann, was the granddaughter of John Bartram, the self-taught American botanist of the colonial era. In June 1829, Carr entered the plant as “a new Euphorbia with bright scarlet bracteas or floral leaves, presented to the Bartram Collection by Mr. Poinsett, United States Minister of Mexico,” at the Pennsylvania Horticultural Society’s flower show, where it was seen and admired by hundreds of people.

Robert Buist, a Scottish nurseryman in Philadelphia, took the next step in its dissemination. He was so enthralled by the new plant that he took cuttings to his friend James McNabb in Edinburgh. From Scotland, it reached the distinguished German botanist Karl Willdenow in Berlin, who named it Euphorbia pulcherrima, in 1834. This remains the accepted botanical name. Two years later, Robert Graham in Edinburgh published his taxonomic findings and changed the name to Poinsettia pulcherrima.

Another myth pertains to how Willdenow came to study the plant. It is said that the plant somehow crept into his greenhouse through a hole in the wall, but the present director of the Berlin-Dahlem Botanical Garden, Dr. H. Walter Lack, told me that he considers this story to be completely false.

Charming and delightful as this tale of the poinsettia might be, the actual facts are as follows: The plant is endemic to southern Mexico. Specimens arrived in the United States in 1828, and by 1829 it was on display in Philadelphia. Its arrival was associated with the name of Joel Roberts Poinsett. From Philadelphia, it crossed to Scotland, and then to Germany. There is no evidence that the plant was ever in Charleston, South Carolina, before reaching Philadelphia, but its movements after Philadelphia are well documented.

When J. Fred Rippy wrote a biography of Poinsett in 1935, he devoted one paragraph to the poinsettia story and indicated in a footnote that he had been unable to find any correspondence to validate the claim that Poinsett had introduced the plant. He commented drily that “it is generally acknowledged in the horticultural guides that Mr. Poinsett introduced the flower.”

Rippy cited the only reliable document of the era, a discussion of Poinsett in the 1887 Charleston Yearbook by Charles Stille, who had spent a day with Poinsett as a lad of twelve. Poinsett took the young boy with him when he visited the Reverend John Bachman, a Lutheran minister and noted naturalist who once worked with Audubon. The Yearbook article states: “Mr. Poinsett was rewarded for the interest he took in science by having a beautiful flower named after him.” There is some “difference of opinion as to whether Mr. Poinsett discovered it himself or simply introduced it to this country. At all events it is always known now as being named after him.”

At the time, the flower was called either “Mexican flame flower” or “painted leaf” in the United States. Neither of these seemed satisfactory, and this is a rare occurrence of a plant acquiring an enduring common name after it received its formal name, rather than the other way around. The choice of Poinsett’s name is often attributed to William Hickling Prescott, the author of the classic book The History of the Conquest of Mexico, but this too is a myth, since Robert Graham used the name Poinsettia in his taxonomic identification of 1836.

Poinsett was a very well-educated, cosmopolitan Southern gentleman of Huguenot descent from Charleston, South Carolina, who spoke French, German, Italian, and Spanish. He was appointed the first American minister to the newly independent Mexico by President James Monroe in 1825, but was recalled by President Andrew Jackson in 1830. Poinsett subsequently acted as secretary of war in President Martin van Buren’s cabinet after serving terms in the South Carolina state legislature and the U.S. House of Representatives. He wrote a book about his first tour of duty in Mexico, Notes on Mexico (1822), with no mention of the plant.

Poinsett never enjoyed very robust health. He started out to be a physician like his father but could not complete the course. His lifelong interest in natural science stemmed from the preliminary studies he did finish. While in Mexico, Poinsett carried on an extensive correspondence about horticulture, exchanging seeds and cuttings with friends and colleagues in the United States. He also believed that the exchange of plants and seeds helped to promote stronger ties between the United States and Mexico.

Joel Fry notes that the American Philosophical Society in Philadelphia elected Poinsett to membership in 1827. This broadened his correspondence to include members of the society and other Philadelphia savants. These connections appear to be the most likely route through which the new plant with bright red bracts reached the United States. There are fairly strong indications that it traveled directly from Mexico to Philadelphia, as four different collections of Mexican seeds and plants were dispatched to Philadelphia between 1828 and 1829.

William Maclure, the president of the Academy of Natural Sciences of Philadelphia, and Thomas Say, a descendant of John Bartram, visited Poinsett in Mexico for three months in January 1828, traveling to Veracruz and Mexico City. Later that year, Maclure visited Poinsett again, and returned to Philadelphia in the fall with many seeds and plants. Say also collected more than a hundred types of seeds but was not meticulous about identifying them. Number 65, a “Fine Red flower, perennial,” could be poinsettia.

In November 1828, James Ronaldson, a Scottish enthusiast in Philadelphia, wrote to Poinsett, who had remained in Mexico until 1829, that he had received a box of seeds from Veracruz and assumed it had come from him. The fourth possibility was William Keating, a geologist who went to prospect in Mexico and met Poinsett. On occasion, Keating acted as Poinsett’s courier.

In summary, there is no doubt that the plant was being grown in Philadelphia when Colonel Robert Carr exhibited it at the first flower show of the Pennsylvania Horticultural Society in June 1829. Poinsett was still in Mexico, but it was generally accepted that he had had a lot to do with the plant reaching the United States. Perhaps the following extract from a letter from one of Poinsett’s friends in 1830 clinches the argument that these plants did not enter the United States via South Carolina. The letter discusses a woman from Charleston: “Mrs. Herbemont has been very vexed with you when she learned by the papers that several northern gardeners had received seeds and plants you had sent them from that land of vegetable beauties, Mexico, and that you had not in one instance remembered her.”

The Poinsettia in Mexico

The specimen received in Philadelphia was not a wild plant but had been cultivated and modified for many years in its native Mexico. Doña Fanny Calderon de la Barca, wife of the Spanish minister to Mexico, commented in her letters home that her church courtyard was lit by these gorgeous scarlet flowers at Christmastide. For reasons that are not clear, Mexican growers still believe that Poinsett devised a hostile mechanism to prevent them from developing or benefiting from the plant’s popularity, purely out of spite. Various publications in Mexico state that Poinsett obtained a “patent” in the United States, which led to this embargo.

Numerous scholars have searched through old patents and treaties but failed to turn up such an instrument. Although U.S. patent laws began in 1795 to protect inventors against their mechanical devices being pirated, these laws did not cover plants. The first U.S. law that did protect new cultivars of plants, the Townsend-Purnell Act of 1930, excluded seed-propagated plants, tuber-propagated plants (other than potato), and wild plants.

At present, international protection for plants is controlled by treaty (International Union for the Protection of New Varieties of Plants, or UPOV, adopted in 1961). Seed-propagated plants in the United States are protected by the Plant Variety Protection Act of 1970, administered by the U.S. Department of Agriculture (USDA). Poinsett did negotiate a commercial treaty with Mexico as part of his ministerial duties, and it was ratified by the United States, but the poinsettia was not part of the treaty. Modern twentieth- and twenty-first-century poinsettia cultivars are protected by patents, but these are relatively recent advances.

Mexican animosity toward Poinsett has some basis in fact and this may have contributed to the myth of the U.S. patent. Poinsett was a very upright, even self-righteous, man and took his duties seriously. This led him to meddle in Mexico’s internal affairs, supporting one party over another, clearly an infraction of diplomatic rules. At one point, there were even death threats against him. All this contributed to his recall by the American president. The term poinsettismo is still in use today in Mexico to express arrogance and high-handedness.

The Poinsettia in the United States

North American nurserymen began to propagate the poinsettia rapidly and distributed it widely throughout the United States over the last part of the nineteenth century. The modern phase of poinsettia development took place in the United States by the early twentieth century. Poinsettias have led the sales of potted plants year after year, and the poinsettia is now one of the mainstays of the commercial flower market. This phenomenal growth is associated with the Eckes, a German immigrant family that settled in southern California in 1900.

Albert Ecke and his family stopped over in California in 1900, en route to Fiji, where they planned to open a health spa. They saw such an excellent opportunity in California that they settled there instead, with their descendants remaining through the present day. Albert began farming in the Eagle Rock Valley, near Los Angeles, but then moved to Hollywood. The family planted orchards and also large fields of chrysanthemum, gladiolus, and poinsettia for the cut flower market. By 1909, they had narrowed their floral crops down to poinsettia alone. Ten years later, both Albert and his eldest son, Hans, had died, and the business was taken over by the second son.

Paul Ecke Sr. moved it south to Encinitas, where it remains today. Paul Ecke Sr. found some valuable spontaneous hybrids in his open fields, but it was his son, Paul Ecke Jr., who initiated a scientific breeding program. At one point the business was sold to a Dutch horticulture firm, but Paul Ecke III has bought it back and is restarting it.

Three generations of the Ecke family: Paul Ecke (son of Alfred Ecke), Paul Ecke Jr., and Paul Ecke III.

Reproduced by permission of Paul Ecke III

The history of the poinsettia in the United States in the twentieth century has some well-defined landmarks. Major advances came about with the discovery of photoperiodism in plants by Wightman Garner and Henry Allard (1920). This led to the use of opaque black cloth to shorten day length. This was essential because the poinsettia is a short-day plant. The plant flowers when darkness lasts for at least 11.75 hours. It is the length of the night, not the day length, that is critical. Adding lights to interrupt the dark period prevents flowering. Shortening the day length and increasing the dark period induces flowering in the poinsettia. Increasing the day length by supplemental lighting keeps the plant vegetative. Management of day length permits synchronization of flowering in order to get plants to flower for the Christmas season. In all this one must remember that the colorful bracts are the major feature of the plant, not the tiny yellow blossoms in the center. The term “flowering” is used loosely.

The early poinsettias were still very fragile. Their leaves fell off quickly, and the scarlet bracts only lasted for about a week to ten days. It made it very difficult to get them into perfect condition by Christmas. That remained true until the 1950s. The late Lyndon Drewlow, a well-known breeder of poinsettias, recalled that he had to assist his professor at graduate school with shortening the stems manually and performing other maneuvers to get the plants into condition for seasonal sale (Drewlow, personal communication).

Radically different cultivars of poinsettias became available over time and changed the direction of its development. Some of this was due to the establishment of a number of breeding programs across the country in the mid-1950s, including Pennsylvania State University; the USDA Research Center at Beltsville, Maryland; and the University of Maryland. Private companies like Azalealand in Lincoln, Nebraska; Mikkelsens in Ashtabula, Ohio; Earl J. Small of Pinellas Park, Florida; and the Yoder Brothers in Barberton, Ohio, were also very active.

One USDA geneticist, Dr. Robert N. Stewart, separated out the most desirable characteristics, such as large bracts, stiffer stems, new colors, and the ability to last for a longer time, and bred for these. The key cultivars were ‘Oak Leaf’ (1923); ‘Paul Mikkelsen’ (1963); ‘Eckespoint ® Lilo’ (1988); ‘Eckespoint Freedom’ (1992); and ‘Eckespoint Winter Rose Dark Red’ (1998).

At first the Eckes only grew the two cultivars of poinsettia available before 1920: ‘True Red’ and ‘Early Red’. Their neighbors in Southern California used these plants to ornament their gardens. ‘Early Red’ was more useful for commercial purposes both as a cut flower and as a potted plant because it held its foliage longer. Three new cultivars were released in the 1920s, but just one of them, ‘Oak Leaf’, introduced by a Mrs. Enteman in Jersey City, New Jersey, dominated the field for the next forty years.

It was the first cultivar suitable for growing in a pot and also retained its leaves and bracts for a longer time. The other two, a 1920 sport, ‘Hollywood’, with wider, more compact bracts than ‘Early Red’, and the 1924 ‘St. Louis’ from Louis Bourdet in St. Louis, Missouri, did attain some popularity in their day. Paul Ecke devoted himself to selecting and developing better cultivars based on ‘Oak Leaf’. His introductions included ‘Henriette Ecke’ (1927) and ‘Mrs. Paul Ecke’ (1929). The latter, a sport of ‘Oak Leaf’, was shorter and had wider bracts than its parent.

Peach poinsettia.

By the late 1920s, poinsettias had become a commercial reality, and several firms across the United States grew them successfully in greenhouses. In Indianapolis, Baur and Steinkamp came across another sport of ‘Mrs. Paul Ecke’, which they named ‘Indianapolis Red’. Each of these sports offered improvement in habit and bract size.

Not all the new cultivars lasted well, despite their undoubted novelty. For example, the offspring of ‘Henriette Ecke’, a cultivar with “double” incurved bracts, which made the plant almost look like a dahlia, seemed very promising, but the bracts were deemed to be too small and the plants did not perform well in the greenhouse.

Demand has since risen for novelties, such as ‘Winter Rose Dark Red’ (1998), the first cultivar to have “curly” incurved bracts and very dark, incurved foliage. By 2004 it was available in seven different colors. Another series with curly bracts, Renaissance, came in at about the same time, specifically for the cut flower market. These varieties do very well as cut flowers.

Although the public finds new colors and styles very exciting, the traditional red poinsettia has remained popular, with desirable traits continuing to be developed. ‘Paul Mikkelsen’ from the Mikkelsen nursery in Ashtabula, Ohio, had a stiffer stem and greater longevity than any preceding cultivar. Eckespoint ‘Lilo’ was the first poinsettia with dark leaves and early flowering. It retained its foliage well but needed some special treatment to ensure good branching. Eckespoint ‘Freedom’ had all the above good points but more consistent branching. It was also ready to be shipped a week or two before Thanksgiving, allowing for a head start on the holiday marketing season. Another excellent quality was its ability to withstand careless handling by untrained staff at large nonspecialty stores.

Breeders have to respond to these needs and accommodate the public’s slightly fickle reactions. Since 2002, Ecke has introduced Eckespoint ‘Plum Pudding’, with purple bracts; Eckespoint ‘Chianti’, with darker wine-red bracts; Eckespoint ‘Shimmer Pink’, pink with white flecks; and many others. Eckespoint ‘Prestige Red’ has become the standard modern cultivar, and it already has many variations.

Poinsettias are no longer grown in the continental United States on a large scale. Almost all cultivation is now done in Central and South America. It is cheaper to grow the plants there because the climate is warmer and the cost of labor is lower.

The Poinsettia in Europe

The poinsettia was widely distributed across Europe by the mid-nineteenth century. It enjoyed great popularity for the same reasons it was so successful in North America, but because the plant had to be grown in heated greenhouses, it was an expensive luxury. Thormod Hegg, a Norwegian breeder, introduced ‘Annette Hegga Red’ in 1964. Hegg found that pinching the stem during development stimulated the growth of more than one inflorescence. There could be as many as eight of them. Hegg’s cultivars also came in a previously unknown range of colors. In addition, it was easy to propagate and grow commercially. The line lasted until 2002.

The Zeiger Brothers in Hamburg, Germany, instituted a breeding program. Gregor Gutbier, in Linz, Austria, introduced another dazzling series of colorful cultivars, the V-14 Glory Angelikas, in 1979. Ten years later, these plants reached the United States. One advantage they offered was an ability to withstand slightly cooler night temperatures. Gutbier was the first grower to realize that grafting an attractive plant with good bracts and branching onto a less well branched plant led to more uniform and successful results. Grafting was very important during the 1980s. Once the role of the virus was recognized, many more breeders were able to produce reliable new cultivars, and the market shares were redistributed.