Tom Wheeler is standing among 13 of the 25 or so varieties of big, lush poinsettias he grows in the vast greenhouses of his employer, Bell Nursery in Burtonsville.

Two or three of them are old varieties — “old” as in poinsettias that have been around for a mere decade or so, but the others are new kids on the block.

Sparkling Punch has big pink blooms with creamy centers; Cinnamon Star has petals — technically, colored bracts — that start lime green before turning to a rich salmon. Visions of Grandeur is full of ruffled, soft-pink blossoms above apple-green leaves. Traditional red bloomers remain the definitive holiday poinsettia, but one in three of Wheeler’s poinsettias is not red.

Novelty poinsettias reflect the most obvious evolution of the plant in recent years, but they are part of a much greater transformation since Wheeler first raised them 30 years ago. Apart from their greater variety, poinsettias have generally become a tougher, longer-lived and ubiquitous mass-market item.

Once a high-maintenance, two-week wonder in mid-December, the poinsettia makes its flamboyant entrance in time for Black Friday and struts its stuff well into the NewYear. This may be good news for the consumer, but for the poinsettia the advances have been a lifesaver.

The Marbella variety of poinsettia. (Matt McClain/The Washington Post)

“It was in a state of decline,” said Gary Vollmer, product manager for Selecta, a major breeder and producer of poinsettias for growers such as Bell.

Commercial poinsettias are raised from cuttings planted in early summer. The poinsettia’s fortunes today are based on a watershed discovery several decades ago, when breeders figured out how to make the cuttings branch — a breakthrough that allowed growers to produce more floriferous pots with fewer cuttings. (Wheeler’s 10-inch pots contain just three cuttings, which produce a total of 20 or more blooms).

But it has been advances since 2000 that have breathed new life into the holiday-season icon. Breeders have been building on early work in Europe to extend the shelf life of poinsettias by selecting a number of related traits. The earliest forms of potted poinsettia, introduced by a California grower in the 1920s, would look primitive compared with the 21st-century article.

Even compared with just a few years ago, today’s varieties have branches that are more upright (less stress for sleeving), have longer-lasting cyathia (the yellow buds in the center of the bracts) and have bracts that are relatively small and stick out (rather than down) to reduce damage.

At Selecta, hybridizers simulate the rigors of interstate truck shipping, warehouse storage, temperature fluctuations and crowding in plastic sleeves as part of the evaluation of commercial candidates, Vollmer said.

Poinsettias color up — ripen, in growers’ parlance — in response to the shorter day lengths of fall. Previously, growers had to fool the plants into thinking autumn had started early by shading them with black cloth. Today, hybridizers have bred early-season coloring into them naturally.

All these advances have fostered not just an earlier start to poinsettia season but also development of a mass market for an item that was once a premium article of the florist.

The Sparkling Punch variety of poinsettia. (Matt McClain/The Washington Post)

Bell greenhouses in Maryland, Virginia and Ohio supply 178 Home Depot stores from North Carolina to Philadelphia, and large-volume growers such as Bell will furnish American consumers with 80 million poinsettias between now and Christmas.

This week marks the prime shipping period for Bell — next week will be the peak sales week, much of it driven by sales of poinsettia gifts (predominantly of safe red varieties).

The shift to mass-merchandiser sales has also influenced the size of plants and the breeding programs that support them. The Black Friday loss leaders tend to be in four- or six-inch pots, while the upsizing of larger poinsettias, from eight- to 10-inch pots by Costco a few years ago , created a new marquee norm for the big-box sellers, Vollmer said. Because both of those types tend to be red, the proportion of red poinsettias nationally has climbed to about 85 percent of all poinsettias.

But Wheeler said his percentage of reds has dropped to 65 percent as novelties have come to the fore in Bell’s Mid-Atlantic market.

Some of them are not to my taste — I find the hotter pinks a bit tacky, even with variegation — but no one can deny the eye-catching and festive qualities of a series of similar varieties known as jingle poinsettias — they have oaklike leaves and spotted red and creamy yellow petals. One variety is Red Glitter, another is Sonora White Glitter.

Whites can look elegant, but finding a true, clear white is difficult. Poinsettia genetics tend to produce whites that lean to green and others that lean to beige, the latter having a yellow cast to them. I happen to like both, though perhaps not next to each other.

At the Smithsonian’s production greenhouses in Suitland, horticulturists Melanie Pyle and Jill Gonzalez showed me Whitestar, a large-flowered bright white. Whitestar was used extensively for spray-painting when that was a fad. Some retailers still gussy up poinsettias with dye and glitter, but that seems to have retreated to a small segment of the market.

Among the brighter whites, Wheeler commends Polar Bear and Arctic White, a later poinsettia that is pleasantly creamy and with green venation as it colors up, though the bracts are on the small side.

There has been much breeding also of the dominant red varieties, again for the traits that growers and retailers are looking for. In some trials, Wheeler said, the color differences in red varieties can be extremely subtle. He grows, among others, Jubilee Red, a strong medium red; Early Orion Red, a rich scarlet poinsettia grown for its early coloring; and Freedom Red, a classic dark red poinsettia.

Culturally, Europeans tend to like the brighter scarlet forms. In North America, consumers favor a deeper, crimson-hued poinsettia, especially if the green leaf color is also a darker shade. But tastes are individual.

When it comes to non-red varieties, breeders are keen to find a better white. The purest whites tend to have thin petals, which makes them prone to damage. Because whites make up 10 percent of sales, the discovery of a tough but clear white variety could capture much of that market. “From a breeder’s perspective, that’s the target everybody is going after,” Vollmer said.

The other is to find a better maroon-purple. The dominant variety is Cortez Burgundy, which has “beautiful color but a lot of production weaknesses,” he said. Visions of sugarplums may dance in our slumbered heads, but there are some people out there who dream of a purple-petaled poinsettia that grows willingly and can take the rough and tumble of the modern marketplace. “We have been desperately trying to get one for a few years,” he said.

How to care for your poinsettia

● Buying

You can tell the age of a poinsettia by the stage of development of the green and yellow buds in the center of the “blooms.” These are the true flowers, and the tighter they are, the younger the plant. Poinsettias dislike temperatures below 50 degrees, so they should be taken home in a protective wrapping and certainly not left in a car while you go shopping for two hours.

The colored bracts and leaves bruise easily, causing the milky sap to bleed, so they should be handled with care.

● At home

Poinsettias like a room with bright, indirect light and temperatures below 70 degrees. Keep them away from drafts and sources of heat. They need moderately moist but not wet soil. The pots should not get too dry; don’t wait until they wilt badly before watering. Decorative foil will impede drainage, so you should either make holes in the bottom of the foil, remove it when watering or take it off altogether. Rest the pots on a saucer.

● After the holiday season

The effortto get poinsettias to survive, regrow and “re-bloom” is burdensome and only worth it if you like a green-thumb challenge. They color up after nine weeks of shorter days following the autumn equinox. If you want blooms before next Christmas, you must keep the plants indoors in a place where they will get light during the day but none after dark. Leaving a light bulb on by mistake will mess up the schedule. You could move your poinsettia plant from a bright room to a closet every day at dusk and back again at dawn, or you could get a life.

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