Sauk County Gardener: Caring for poinsettias

“Flowers are like friends; they bring color to your world.”– Unknown

A favorite holiday plant for many people is the colorful poinsettia. For me, there is no other flower that says Christmas quite as well as the poinsettia with its beautiful red flowers and dark green foliage. Every year, I typically purchase one to grace my kitchen counter and enjoy it well into January when I care for it properly.

The poinsettia is a perennial native to Mexico and can grow into a shrub that is nearly ten feet tall. On poinsettias, what we typically consider to be flowers are not really “flowers” at all. Instead, they are colorful bracts (modified leaves) that are arranged around the actual little yellow flowers (cyathia) in the center. This beautiful plant was introduced to the United States by Joel Roberts Poinsett, a botanist, physician, and the first U.S. Ambassador to Mexico. Dec. 12 is designated as Poinsettia Day, marking the death of the botanist in 1851. The flowers come in a wide range of colors from the traditional red to pink to a creamy white. You may even find some with patterned leaves such as red and white, or spray painted in colors of blue, purple and more. Even with all the new colors being introduced, red is still the favorite for many people.

This plant, like others in the Euphorbiaceae family, has a milky sap. Keep in mind, if you have a latex allergy, it may cause a skin reaction such as a rash after touching the sap or leaves. The sap can also be an irritant or cause nausea, so it is best to keep it away for your pets. The leaves have a terrible taste; however, the plant is not poisonous.

There are few things to look for when selecting a Poinsettia that will help ensure it lasts the entire holiday season. Plants will drop its leaves as soon as it sheds it pollen, so look for one with little or no yellow pollen showing. Also look for one with dark green foliage all the way down to the soil line, that its bracts are completely colored, and that it is not drooping or wilting. If possible, try to find a plant that was not displayed in plastic or paper sleeves as it will tend to decline more quickly. Also try to avoid ones that have been crowded together as it causes the bracts to fall off early. Check to the soil; if it’s wet and the leaves are wilted it may have root rot. Finally, check the underside of the leaves to make sure you’re not bring home any unwanted guests such as aphids and whiteflies. They are very sensitive to cool temperatures so make sure it’s covered as you take to your car if the outdoor temps are lower than 50° F.

When you get your poinsettia to your home, place it near a south, east, or west window where it can get bright light. The ideal temperature is between 60° and 70° F and avoid putting it near a heat vent or cold air return as temperatures tend to fluctuate or are drying in these locations. The soil should be moist and the plant should be watered when the soil feels dry to the touch. Don’t allow the poinsettia to get so dry that it wilts. If it came in a decorative foil wrapper, remove it before watering so water doesn’t collect in the bottom of it. This will help ensure it doesn’t get waterlogged or sit in excess water which can cause root rot. The easiest way to water it is to place it in your kitchen sink, water it fully and let the water drain out the bottom. I use this watering technique for many of my houseplants. You don’t need to worry about fertilizing your poinsettia until you start to see new growth. When that happens, simply use an all-purpose house plant fertilizer at half strength ever three to four weeks.

With careful selection and proper care, your holiday poinsettia can last six to eight weeks. Getting them to rebloom is a bit more challenging. However, if you’d like to try to get it to rebloom, visit http://pss.uvm.edu/ppp/articles/poinsett.htm for more information on year-round care.

Extension Sauk County is hiring a horticulture educator. Visit our website at sauk.extension.wisc.edu for details.

Remember to contact the University of Wisconsin Madison Division of Extension Sauk County staff if you have any gardening questions. Please send an email to haley.weisert@saukcountywi.gov or call the University of Wisconsin Madison Division of Extension Sauk County office at 608-355-3250.

Jeannie Manis is president of the Sauk County Master Gardeners Association (SCMGA).