I got the first blooms about 4 years after I planted it, and I've come to rely on it as a very dependable barometer of when spring has arrived. When these bloom, it's safe to plant outside.
Currently, it's 4 trunks, the tallest at six feet, the shortest at 4. We're in the northernmost reach of it's range, so I'm pretty sure that I won't get the 20 foot tall trunks that the plants can develop further south, but I'm hoping for 10 feet or so eventually... When it reaches it's maximum height, it'll fall over. Then the growing tip will turn to point up and it'll continue growing, with more plants growing up from the roots... Eventually, they can form dense, inpenatrable thickets.