The Joshua Tree is the most common variety seen grown as a tropical houseplant. Perfect for adding a tropical feel to your indoor space, these plants are fun and relatively easy to grow. The leathery, sword like leaves arch and will eventually yellow and fall off, replaced by the new top growth, this increases the height of the plant. The exposed trunk is certainly attractive adding texture to the plant. This plant will thrive in direct sunlight or bright, indirect light. Well draining potting soil is best, with good drainage holes in the pot as well. When the soil has completely dried out, water evenly until water runs through the bottom of the pot.