I have a couple Anthuriums that have done well for me for quite a while now, but they've gotten tall, to where there are a few inches of bare stem at the base of the plants, before the leaves begin. What's the preferred method for dealing with this? Can I bury them deeper? Do I need to cut them back and re-root them? The plants in question are blooming like crazy now (both of them have had four or five blooms at a time since about September), so I would rather not do anything that's going to traumatize them. Suggestions?