TRANSPLANTED GARDENER

By Sherry Rindels-Larsen

Receiving or buying a poinsettia is a holiday tradition for many of us. Poinsettias are a holiday favorite with colors from traditional red to creamy white with varying shades, marbling, and speckling in between. About 90 million poinsettia plants are sold each year (worldwide) with a retail impact of almost 1 billion dollars. While many just toss the plant after the holidays, others accept the challenge to keep them growing and give them what they need to bloom for the next year. If you are up to the challenge here is what you will need to do:

Poinsettias are sensitive to temperature extremes. Keep them indoors if nighttime temperatures are below 45 degrees. Once the nighttime temperatures are consistently in the 50’s, put the plant outdoors in a sunny spot. When nighttime temperatures are not dropping below 80 degrees, it is time to bring the plant back indoors until cooler nighttime temperatures return in September. Poinsettias can’t handle high nighttime temperatures and will fail (collapse and die) when they can’t photosynthesize properly.

Poinsettias do not like to dry out or be over watered. Water plants when the soil surface is dry to the touch and let the water drain through the container. Do not let plants stand in water as this often results in root rot.

Pruning is a necessity. Around Valentine’s Day, trim plants to a height of about 5 inches tall. This is also the time to repot into a larger container and give it

The Holidays Are Through, Now What Do I Do?

some fresh potting soil. Bump the container size up by about an inch or so. Use good quality potting soil that provides good drainage. Around Memorial Day, trim off two to three inches of the plant to encourage additional side branching. Trim two to three inches off again around July 4th. The result of the frequent pruning is a full multi-branched plant.

Beginning in January, fertilize your poinsettia every month to six weeks with a complete fertilizer to encourage new growth. Complete fertilizers contain Nitrogen, Phosphorus and Potassium. Continue fertilizing with a full-strength fertilizer until Labor Day. After Labor Day, reduce the strength of the fertilizer to about ¼ the recommended strength and continue at this strength until January.

Plants will need at least 6 to 8 hours of bright light daily to keep them growing well. A south-facing window would be the ideal location indoors. Outdoor plants can take a sunny location until daytime temperatures climb above 80. Once that happens, move the plant where it will receive partial shade or provide some sun protection during the summer months.

Poinsettias initiate bract coloration (the colored leaves) and flowers in response to short days. Beginning in mid to late September, plants will need 16 hours of uninterrupted darkness each 24-hour period. This does not mean putting the plant into a closet and forgetting about it for several weeks. They still need 8 hours of bright light each day. Some gardeners will set them outside in a sunny location that doesn’t have any “light pollution” and they will initiate color based on our natural day length. Others will cover the plant with a box at night to make sure there is no light getting to the plant for those 16 hours. If given those specific lighting conditions, you should see good color development on the bracts by Thanksgiving. Once the coloration begins, you can discontinue the short day, long night treatment. Plants will continue to develop additional color and by Christmas, you will have a beautiful colorful poinsettia once again.

Keep an eye out for insects such as whitefly, mealybugs, and thrips all of which love to create havoc with poinsettias.

Join the Sonoran Desert Club for their quarterly membership meeting on Thursday, January 19. The meeting starts at 4:30 pm at the Rec 1 Promenade. Everyone is welcome whether you are a member or not.

Sherry Rindels-Larsen is President of the Sonoran Desert Club and a Maricopa County Extension Master Gardener

For additional information on poinsettia and its care visit: https://hortnews.extension.iastate.edu/guide-selection-and-care-poinsettias or https://extension.usu.edu/archive/could-you-should-you-keep-your-poinsettia-year-round or https://theproducenews.com/floral/how-poinsettia-took-over-christmas#:~:text=It’s%20one%20of%20the%20most,impact%20of%20nearly%20%241B.