Yes, it is not so quick to grow for the first 18 months I would say, but summer is coming and it will grow fast! It needs protection during the winter or greenhouse if you want it growing faster. How tall do you want? I can make from 1ft to 3-4ft by autumn and will plant in a 3 gallon pot. $15 now or $100 then. I'm trying to say that you can do the same yourself. Osmocote plus is the simplest way to grow it faster during the summer and also you can get better results doing organic way and with worm castings/ worm tea. It needs everyday or every second day watering and good drainage and some extra fertilizer and filtered light, something like 30% shade cloth, you can try 50-60% shade cloth if you want it taller and leaves greener.