Pointers for keeping potted poinsettias thriving
“We were so happy, happy, I remember
Beneath the poinsettia’s red in warm December.”
— Claude McKay, “Flame-Heart,” in “Harlem Shadows,” 1922
Claude McKay (1889-1948) was an important writer for the Harlem Renaissance movement of the 1920s. McKay grew up in Jamaica, and his poem “Flame-Heart” is a wistful reminiscence of his childhood play in the shade of a Jamaican poinsettia tree (Euphorbia punicea).
McKay’s “flame-heart” is related to one of America’s favorite Christmas plants, the poinsettia (Euphorbia pulcherrima), and both are a type of spurge. Although many Oregonians associate poinsettias with cold winter temperatures, they are native perennials in the warm climes of Mexico, where they grow as flowering shrubs 10-15 feet tall. In fact, poinsettias are named after Joel Poinsett, the first U.S. ambassador to Mexico.
I would like to think I could keep a poinsettia plant alive if I could grow it outdoors. Unfortunately, poinsettias are not winter hardy in areas lower than USDA Hardiness Zone 10, and I have yet to keep any of my potted indoor poinsettias past the New Year.
Could I dare to dream that I might someday wish a happy birthday to a poinsettia plant? I talked with Kelly Brainard, owner of Ashland Greenhouses, and here’s what she suggested for keeping potted poinsettias alive during the winter — and perhaps even beyond!
Remove the foil wrapper around the potted plant and replace with a drip tray that will allow water to drain. Water the plant deeply every 3-4 days until water drains from the bottom of the pot. Don’t overwater your poinsettia, though; allow the plant to dry out some between waterings.
Poinsettias thrive in air temperatures between 65-70 degrees, so you may need to adjust watering frequency according to the air temperature in your home. Brainard said most people are quick to whip out the watering can if they see poinsettia leaves start to curl, but this may mean the plant is getting too much water, rather than not enough.
Place the plant in a sunny window where it will receive the most natural light possible, also out of drafts, off electrical appliances, and away from fireplace mantels.
Nursery-grown poinsettias don’t need fertilizing until May or June. When temperatures warm up in the spring, transplant your poinsettia to a larger pot, freshen up the soil, and begin adding a balanced N-P-K fertilizer weekly that will help maintain the color. By the way, the colorful part of a poinsettia plant is the modified leaves called bracts; the poinsettia’s insignificant flowers grow within the yellow center.
Keep poinsettias outdoors in a sunny location throughout the summer, but it’s a good idea to protect the plant from extreme heat. Continue to monitor the soil so it stays slightly moist. Brainard said to expect poinsettias to go through a “Charlie Brown phase” during the summer when the plant loses its color and doesn’t look that great.
In July and August, cut the poinsettia back to half size, keeping in mind that the number of nodes left on the plant stem will determine how many new shoots will grow from the cut. At this point, the plant will look terrible, but hard pruning will keep it compact and healthy.
Bring the poinsettia indoors in September and place it in a location where it will receive light during the day and darkness at night. Poinsettias need a dark period in order to begin coloring in time for winter home decor. Before bringing the pot inside, be sure to check for insects that have made themselves comfortable on the plant or in the soil.
Like other euphorbias, the latex in poinsettias can irritate skin and cause an upset stomach if consumed; however, it’s a common misconception that the plant is highly toxic.
If all goes well, I’ll have a beautiful, vibrant poinsettia by December. I can be especially proud of the plant for managing to keep it alive year ‘round.
Like poet Claude McKay, with his memories of the Jamaican poinsettias, Brainard and her team at Ashland Greenhouses associate poinsettias with warm temperatures because they begin growing rooted cuttings in July. During the following six months, the poinsettias are their most labor-intensive plants, requiring several handlings to regulate their growth.
By December, Brainard’s greenhouses are bursting with 9,000 poinsettias in multiple sizes and more than a dozen varieties that have festive names like Jingle Bells, Ice Crystal, Sonora White Glitter and Peppermint Ruffles.
It’s nice to know there’s a Plan B if growing poinsettias myself doesn’t work out.
Rhonda Nowak is a Rogue Valley gardener, teacher and writer. Email her at Rnowak39@gmail.com. For more about gardening, visit her blog at http://blogs.esouthernoregon.com/theliterarygardener/.