Yucca Rostrata will grow a trunk up to 18 feet tall and looks similar to a palm tree. They are slow growing, about 2 to 6 inches of trunk each year once the plant begins to produce a trunk. The key to growing this plant is good drainage. It likes full sun and dry soil that quickly drains. We add lime stone gravel to our plants which helps with drainage. It is one of the most cold hardy plants that grows a trunk and stays evergreen. Some leaf damage can occur if temps get really cold. Our plants have survived -14F.