How do you take care of a poinsettia after it’s done blooming?
The Gardener’s Answer
Euphorbia pulcherrima, commonly known as poinsettias, are a traditional Christmas decoration. There are now a variety of colors available, including different shades of reds, pinks, and cream. These Mexican natives prefer to grow in a sunny window with an air temperature no less than 60 degrees F. A watering schedule will depend on the temperature and humidity of your home but in general they should be watered every seven to 10 days or sooner if the soil is dry. They do not like to have wet roots so keep the soil on the dry side as opposed to over-watering, and make sure the container has sufficient drainage. As for getting your poinsettia to re-bloom, this can be done but it requires more than just patience.
If you would like to try to get it to bloom again next Christmas you will want to continue watering on a regular basis until early April. Then it will need to go through a drying phase where it should be kept in a space where the air temperature is as close to 60 degrees F as possible and has good circulation. When the middle of May arrives you will want to cut back the stems to about 4 inches, repot with a good quality container mix, and water it well. Move it to a warmer location, preferably a south-facing window, and wait for it to put on new growth; when it does go ahead and give it a dose of your favorite water-soluble fertilizer and repeat every two weeks. In June you should move the plant outdoors to a sunny location, continuing to water and fertilize. In early July pinch back about one inch of each stem and do this again in late August, leaving only three to four leaves on each stem. At this time you can bring it back indoors and place it in a sunny window.
When October arrives the plant will require complete darkness from 5 p.m. until 8 p.m. each day; otherwise it should be in a sunny window. To get the poinsettia to re-bloom around Christmas time it will need this daily dark time until Thanksgiving. Continue to fertilize until mid-December and once again enjoy the blooms. Some would consider the poinsettia to be disposable after the holidays; in some cases it is easier to leave the work up to the professional growers and then purchase another one the following season.