Yes, in the beginning I have been trying to poke wingless drosophylla flies
in the pitchers, till I decided to try liquid fertiliser. Now I use diluted
orchid fertiliser, both in the greenhouse and on the plants coming out of
tissue culture. Pitcher growth is super, and the plants trive. I think we are
over-caring too much with nepenthes, and statements like /* they don't take
fertiliser, insecticide, low humidity...*/ date back from the days when only
a small amount of nepenthes were in culture.
The only determining factors I have realy seen are temperature (some species
do fold back below 15 deg C) and to a lesser extend light. Humidity can drop
below 70%, and I had cases where the substrate went dry because the
sprinklers were down for three days. This only resulted in a lot of the
plants producing side shoots. Even in Nature nepenthes do not always live in
the pampered conditions we try to produce in our greenhouses. They are much
more resistant than we believe.
John De Witte