For many Americans, poinsettias are a symbol of the Christmas holidays. Their radiant color will brighten up your home, even in the dark of winter, and something about their specific shade of red really works for me. The connection of poinsettias to Christmas reaches back to a mexican legend. A young girl had no gift to lay by the manger at her church on Christmas, so as she walked to town she gathered some weeds into a bouquet. As she laid the bouquet by the manger it was miraculously transformed into what we now call a poinsettia.
It's a nice story, but if poinsettias were truly weeds I'd have much less trouble keeping them alive. It can be tough enough just to spell "poinsettia" in your thank you cards - actually keeping these plants alive is a bigger challenge. Or it was, until my wife got two great tips from a guy at the flower shop.
1) Keep it someplace sunny. This time of year it can be really tricky to keep anything in full sun. Additionally, I always picture poinsettias on a mantle or hearth, which aren't usually the brightest places in the room. So pick a south facing window if you have one, and make sure that the plant gets as much light as possible. We had the best luck with ours on top of a bookcase in front of a west facing window. You might not have an ideal location, but work with what you have.
2) Water it from the bottom up. Apparently, poinsettias are easily over-watered, and this contributes to the scraggly look that they often take on. The way to work around this is by watering them from the bottom up. Most of the time when you get a poinsettia, the pot is wrapped in either plastic or foil (or both). Instead of pouring water onto the soil, pour it in between the pot and the plastic wrapping. It will soak in through the bottom of the pot and get to the roots of the plant.
These two bits of advice can keep your poinsettia thriving and colorful for many months. As much as I like them in winter, they look really nice in May or June as well.