If you want to ensure that your Christmas Cactus blooms, there are a couple of things you need to do. First, you need to make sure that it is is getting good light, but the light must be non-direct. If direct light hits the plant daily, it will not bloom. Second, at the beginning of December, add two tablespoons of caster oil to the soil. If your Christmas Cactus already blooms, this will result in better blooms and if not, this will get it to start blooming.