Succulent topiary trees need less care than floral arrangements and last much longer-several months or more. They don't require soil to grow but can be attached to different surfaces and plants to create incredible arrangements. These plants are very easy to care for and look great as ornaments. Once you've got the soil sorted out, you need to make sure you are watering appropriately. The soil should be mounded at the back the same as the sand. Combining several different kinds of sand in one pot will result in a plant that looks large and lush with many bright blooms.