Put the plant outside after danger of frost has past. Come summer, move your potted poinsettia outdoors. The Dos Donts Of Poinsettia Care Christmas Plants Poinsettia Care Christmas Plants Poinsettia Take note that you can keep your poinsettia outside if the summer temperatures are warm enough and don’t drop below 65 degrees. How to care for poinsettias in summer . After the holidays, keep poinsettias warm and moist. Water your potted poinsettia when the soil starts getting dry and place it in a sunny location in your home, protected from air currents. Constant wetness will rot plant roots. The plants sort of grow themselves with only a little care. Summer poinsettia yields flashy color Cut the poinsettia plant back half way in april. If you put them outside for the summer, make sure they are in partial shade. Let it grow actively during summer, watering and fertilizing regularly as you did in the spring. Once summer is in full swing, move the plant to an outdoor a...