Poinsettias (Euphorbia pulcherrima) are stunning to behold at Christmas, making popular decorations and gifts. What most people call blooms on a poinsettia are actually colorful leaves called bracts. The flower is the small yellow dot that sits on the middle of the bract and isn't very showy at all. Whatever you call these colorful leaves, you can help them stay beautiful longer by properly watering and caring for your poinsettia.
Watering Your Poinsettia
As tropical plants, poinsettias like moist soil, but they don't like sitting in water. Remove the decorative foil from your plant or poke holes in it promptly so your plant gets proper drainage when watering your poinsettia. Keep the soil moist but never soggy. In some houses, weekly watering will do, but your plant may need more water, especially if your home is dry.
When watering poinsettias, place your plant in the sink. Run water down into the pot, avoiding the plant's leaves as you do so. Continue to water the plant until water drains steadily from the bottom and then allow your plant to continue draining until it stops on its own. If you set your plant in a dish to catch any drips, be sure to empty it whenever it collects water.
The Right Location
When blooming, poinsettias thrive in temperatures between 60 and 70 degrees Fahrenheit. Warmer temperatures can shorten a plant's bloom time, and colder ones can shorten its life. For best results, place your poinsettia near a sunny window where there is no draft. Make sure the plant doesn't actually touch the window pane, as this can make the plant too cold.
Poinsettias are short-light plants, meaning they respond to and bloom during shorter days. If you want to keep your holiday plant looking good for longer, place it in a dark room each night where the temperature is between 55 and 60 degrees Fahrenheit. Don't fertilize it while it's in bloom, however. Doing so provides no benefits.
Make Your Plant Bloom Again
For many people, a poinsettia's life ends in four to six weeks when the holiday season is over, and the plant's colorful bracts fade. If your plant was particularly lovely, however, you can keep it and encourage it to bloom again next year. Keep taking care of the plant as you have been until February or March. At that time, cut the flowering stems back to a length of four to six inches.
In the spring, repot your poinsettia. Continue watering the poinsettias, keeping the plant's soil moist and fertilize the plant every two weeks using a soluble 20-20-20 fertilizer. You can keep the poinsettia indoors or dig a hole in your garden and drop the entire pot into it. If you do, wait until nighttime temperatures remain above 60 degrees Fahrenheit, choose a location with morning sun and rotate the pot periodically so the plant's roots don't grow through the pot's drainage holes and into the ground.
Bring your poinsettia back inside before fall temperatures start dropping below 55 degrees Fahrenheit. Beginning in late September, start covering your poinsettia with an opaque bag or placing it in a dark closet every night for 12 to 14 hours. Continue to do this until the colorful bracts come back in December. Stop fertilizing the plant once it blooms.
Poinsettias as Garden Perennials
If you live in a frost-free area inside U.S. Department of Agriculture plant hardiness zones 10 through 12, you can grow a poinsettia outdoors as a perennial plant for many years. Choose a sunny location that doesn't receive artificial light at night. Make sure your poinsettia is protected from wind in its new home and that the soil drains well. Provide plenty of headroom too since garden poinsettias can easily reach heights of eight to 10 feet.
To keep your plant from getting too leggy, prune it every two months. For more colorful winter bracts and a bushy appearance, pinch back the top quarter-inch of new growth once a month in the summer. You can fertilize outdoor plants with a liquid fertilizer every other week from spring until fall or use a slow-release, granular fertilizer every six to eight weeks.