Poinsettias are beautiful potted plants that many of us receive each year in December. While they are gorgeous, their bloom is often temporary. The plant seems to wither and fade, and is eventually tossed to the curb. If you enjoy a challenge, you can try to keep your poinsettia blooming year after year, but you must follow some very specific instructions.
Place the plant in a sunny window, preferably facing south or east, that will allow it at least 6 hours of light each day. Do not let the plant touch the cold glass or windowpane, as it can cause damage. It is also important that it not be in a draughty area.
Maintain the temperature, where the poinsettia is located, between 18 and 21 degrees C. Poinsettias do not like extremes in temperature.
Keep the plant well watered, but allow the water to drain well. If you have the plant still in the pot and foil wrap that it came in, poke holes in the foil so the water can drain onto a saucer. Dump the water from the saucer, and do not allow the plant to sit in standing water. According to the Ohio State University Extension Service, leaving the plant in standing water can lead to root rot.
Continue maintaining and watering the plant until April, at which point you should allow the soil to dry out somewhat. Do not allow the soil to become so dry that the plant starts to wilt.
Cut the stems back to 4- to 6-inches tall in May, and then remove the plant from its current pot and transplant it into one that is 2 inches bigger in diameter. Re-pot the plant in new soil, preferably a potting mix for indoor plants. Water the soil thoroughly as soon as you have replanted. Place the plant back in the sunny window.
Fertilise the plant, with a fertiliser for flowering plants, when new growth begins to show. Use the fertiliser every two weeks.
Move the plant outside in June, and set it in a shady area. Continue to water and fertilise it regularly.
Pinch off 1 inch of new growth from each stem, beginning in July. In mid August, cut back the new stems so that there are only four leaves on each stalk. The purpose of pinching the stems is to keep the poinsettia from growing too tall. Do not pinch any stems back after September 1, as this allows the plant to get ready for its winter bloom.
Bring the plant back inside and place it in its sunny window location. As a final preparation for its winter bloom, the Alabama Cooperative Extension explains that it must be exposed to shorter days of sunlight, beginning October 1. To do this, make sure your poinsettia is in a completely dark area every day from 5 p.m. until 8 a.m. In the morning move it back to the sunny window, and return it to darkness in the afternoon. It is important that between the hours of 5 p.m. and 8 a.m. the plant is not exposed to any light whatsoever, or you may compromise your bloom.
Enjoy your bloom in December, and then repeat the steps to enjoy them again the next year.
For an interesting and sentimental gift, when the poinsettia blooms the next year, pass it back to the person who gave it to you with instructions on how to care for it. See how many years you can keep it going.
Realise that the blooms on a re-potted poinsettia may not be as bright and spectacular as they were in its original year.