An academic approach to the Christmas plant

Dec 23, 2016  | 5 min  | Ep4218

According to the National Christmas Tree Association, 25 million fresh cut trees with a price tag of more than a billion dollars were sold in 2015. A good share of those trees were sold to families in search of the perfect Tannenbaum.

But holiday horticulture comprises more than just the venerable tree. Plants and flowers of various types also are responsible for proclaiming the season.

Just getting those trimmings to market involves more than meets the eye. And in one case, teachers are using the lesson of hard work as an academic pilgrimage.

Paul Yeager explains.


The Christmas tree gets the lights and songs, but not everyone cuts down a live one and puts that in their home.

The one embracing the colors of Christmas is the Mexican transplant, the poinsettia. Brilliant bracts of green and red, white, or pink -- the plant has more than 100 variations.

Randall Vos, DMACC Horticulture Department: “Blooms naturally around Christmastime which made it a good fit for the holidays, blooms based on day length, don’t have to manipulate it too much to get it to flower, but, it’s also the traditional Christmas colors.” 126

Those colors have evolved as the plant has grown in popularity. More than 30 million are sold each year according to USDA – almost ¼ of all flowering potted plants purchased -- to rack up more than $144 million in sales.

The poinsettia first came to the United States in 1825, but only set roots in our lexicon during the 1960s. The lobster flower or flame-leaf flower as it’s also called -- is found almost anywhere from churches to homes.

New varieties emerge every year as hybrids take hold… and science works most of the time…

Randall Vos, DMACC Horticulture Department: “There will be a slight difference, maybe the bract color is darker or you’ll have 1,000 white plants and one is pink. A lot are just natural mutations where we did some cross pollinating to get one variety and it just naturally mutated, that’s very common in plants.”

Randall Vos is the Horticulture program chair at Des Moines Area Community College in Ankeny, Iowa. Annually he leads a class that grows the poinsettia from sprig to sale.

Randall Vos, DMACC Horticulture Department:  “Our main goal with the poinsettias is to get the students a hands on class. We don’t have any tests in this class, it is all in how your plants turn out.”

The customers are usually faculty or staff on campus. Vos, who has a background in commercial horticulture, helps students understand the demands of the end user, extending the lesson as growing the best plant root to bract.

Randall Vos, DMACC Horticulture Department: “We test the PH of the media, the salt content of the media, lets us know if we’re fertilizing or not. Every week they have to graph the height of the poinsettia, because we follow a growth curve to see if we’re in line with the height, Some of these varieties we did not stay on top of the heights and they are too tall and that’s part of the grading requirement.”   

Macklin Briggs is one of those students getting his hands dirty in class. He says timing is key as the poinsettia performs better in drier conditions to help the modified leaves form fully.

Macklin Briggs, DMACC Horticulture student: “There’s a science to growing all plants. But with these you want to get spacing right so they grow the right height, and so we get weak stem, and the bracts aren’t fully formed.”

And that knowledge Briggs plans to use in his horticulture career.

Macklin Briggs, DMACC Horticulture Student: “Whatever you learn from growing poinsettia, you’re able to take that and apply to other plants.”

A couple of notes about the poinsettia. The leaves are not poisonous individually… you would need to consume more than 500 leaves to have any harmful effect according to a study from Ohio State University. The same study reveals pets dining on a milky leaf could experience nausea or intestinal irritation.  California is the nation’s top poinsettia producing station in the U.S.

September’s shorter sunlit days signal to the poinsettia it is time to change colors – or bloom.  The internal clock interprets more dark than daylight as the cue to initiate the flower. Greenhouses take precautions to block out any light as to not disturb the cycle.

The window for error is small and can be delicate -- even for seasoned professionals.

Randall Vos, DMACC Horticulture Department:  “The tricky thing about poinsettias is you get only one chance per year, there’s only one poinsettia crop,  so even if a grower’s been working for ten years in a greenhouse, they’ve only grown ten poinsettia crops, most other crops in a greenhouse are grown every year. In the spring, you may get only 5 shots at growing petunias.”

And Vos’ hands-on approach stresses the customer’s expectation - uniformity.

Randall Vos, DMACC Horticulture Department:  “The customer doesn’t know that this plant naturally grows taller, that one grows shorter, it is up to the grower to make everything uniform. 752 So if you look down the bench no matter what variety there is, they’re all the exact same height because that’s what the customer wants. It may be two of these plants together, they want them the same height. 10804 That’s what makes or breaks you.”

For Market to Market, I’m Paul Yeager. 

More from this show

Grinnell Mutual Insurance