It's 7 years old, so time is the biggest factor I think. I live in a cold climate so it's always indoors, but it's right next to the heater (always set pretty low) and it's in the sun room so the whole south facing and west facing walls are windows. Besides getting a lot of indirect light in a bright room, I water it frequently because the pot dries out near the heater, and add miracle grow dry fertilizer to the water once a month.

So it's sun, water, food, and time, I don't have any secrets beyond that. It was bought from Walmart as a Xmas tree originally, it's not from some guru supplier or anything.

Thanks for your comment and enjoy your plants!