Pencil cactus is a great and fun plant to grow both indoors and outdoors. How should you care for it? In the garden it takes full or partial sun. Indoors this is a high light plant – it needs sun & all the natural light you can give it. Make sure it has a south &/or west exposure. If it’s not getting light from all sides, then be sure to rotate it every few months. The water should be low. In your home water it every month or so in the summer and maybe every 2 months in the winter, depending on a few variables. Need more instructions? Head over to joyusgarden.com.