What to do with poinsettias after the holidays

Christmas, like all holidays, is really made of dreams.  Anything is possible during Christmas, and the garden is no exception.

Take a wild weed that blooms in December. This rangy Mexican flower first sold in 1906 at a flower stand in the land of dreams, Hollywood.  The radiant red flowers, actually leaves called bracts, became a staple in California homes, and the once unsought weed with the bright red leaves came to symbolize Christmas in America.  It is, of course, the poinsettia (Euphorbia pulcherrima).

Those showy colored parts of poinsettias that we think are the flowers are actually colored modified leaves, or bracts.  The color is so deep that they are used in fabric dyes. Though some people might get a rash from the sap, poinsettias are not poisonous.  An Ohio State University study demonstrated that a 50-pound child who ate 500 poinsettia leaves might, at worst, have a slight tummyache.

But what to do with your poinsettia after the holidays?  You can toss it into the compost heap, toss it with the torn wrapping paper or keep the plant alive until next year, as a gift that keeps on giving.

Poinsettias do best with daytime temperatures of 60 to 70 degrees and nighttime temperatures about 10 degrees cooler, at around 55.

Because high temperatures will shorten your plant’s life, try to move it to a cooler room at night.  Place your poinsettia in a well-lit spot away from drafts. A south-facing window is ideal.

Check the soil every day, and water about once a week, or when the soil is dry to the touch. Don’t let the soil stay soggy.

From January through March keep watering poinsettias only when the surface of the soil feels dry.   In early April, reduce watering, so that the soil is quite dry between waterings. Do not let the stems get so dry that they begin to shrivel.

After a few weeks of decreased water, move the plants to a cool spot such as your basement or garage. Try to keep the plants around 60 degrees.

In the middle of May, cut the stems down to about four inches.  If needed, repot the plants into pots just two inches wider than the ones they are in.  Begin watering the plants daily and move them into bright light. Keep watering whenever the soil feels dry to the touch.

Your poinsettia will begin growing with the onset of spring and summer.  Fertilize every two weeks with a liquid houseplant fertilizer.

Once the danger of frost is past, you can move your poinsettias outside. Shield your plants from drying winds and keep fertilizing every two weeks. In early July, pinch off an inch from the tip of each stem to encourage branching; otherwise your poinsettia will get tall and spindly.  Pinch back the stems one more time around mid-August.

In September you can bring your poinsettias back indoors.  Keep them in bright light with temperatures above 65 degrees.

Because poinsettias set their buds according to the length of daylight, you will need to give them about 10 weeks with less than 12 hours of sunlight per day.

Since most of us use indoor lighting, it can be tricky avoiding extra light on your poinsettias.  Try keeping your plants in a room that is lit by sunlight during the day, but has no artificial light at night.  You can also move the plants in and out of a dark closet every day.  With perseverance and luck, your poinsettia will bloom for many Christmases to come. Even if your poinsettia won’t rebloom, it will remain an attractive, leafy green houseplant. In the middle of a dark winter, even a leafy green plant can be a Christmas miracle in itself.