I saw this in the BACPS newsletter and I thought I'd share it.
ASSISTING NEPENTHES TO FORM LARGE PITCHERS
I, and a few others, have found a way to increase the pitcher
size in Nepenthes (Tropical Pitcher Plants). By adding a layer
of moist long-fibered sphagnum or live sphagnum under a
developing pitcher, the added humidity seems to help the growth
of the pitcher. As the pitcher grows, you may see that it is
increasing in size. As an end result, the pitcher, when opened,
tends to be much larger then the surrounding pitchers without
this "humidity treatment". I have yet to try this on other
"cup" pitchers (mainly Cephalotus f.), so if anyone is
attempting this, please let me know. Thank you.
Copyright 2003 Zach Lim