Expert: Christopher Littrell - 10/26/2010

Question
Hi!
I have a bicalcarata and it hasn't been growing much.
I heard that it was a really fast grower.
The plant is producing more leaves, but the leaves haven't
gotten any larger!
What am I doing wrong?
The leaves stayed the same size ever since I have gotten the
plant which has been almost half a year.
Also, the tip of the leaves (tendril?) keeps turning white!
I keep the plant with my other neps, facing a north-east
window with two 23 watts lamps.
Thanks!

Answer
Hello Jin,

Well, the first consideration is always light, followed by temperature and humidity in the case of Nepenthes.

What temperatures are you growing the plants in? Nepenthes bicalcarata likes the temperatures warm all year, between 70-85 degrees all the time. If the temperature of the room you have the plants in drops below 70 at night, which is good for the highlander Nepenthes, the lowlanders, like N. bicalcarata will not like it. Conversely, if the temeprature is too hot, it could have adverse humidity effects and dry out the tendrils, particularly if the plant gets too strong a dose of sun at a specific time.

In any event, try increasing the amount of light the plant gets. Optimum indoor windows would be East or South facing. Optimum lighting types would be the long 4 foot twin mount shop lights with cool white 40 watt tubes. Keep artificial lights on for about 12 hours in Winter and 16 hours in Summer and keep the lights about a foot from the leaves or less according to need. I have three such shop lights over my Nepenthes in a side by side arrangement giving about 18000 lumens of light intensity. Both Nepenthes are getting quite large and produce pitchers constantly of larger size each time. Light coverage definitely makes a difference.

Was the N. bicalcarata grown in high humidity before you got it and does the humidity change drastically near the plant in the room it is in? If there are vents from central air and air conditioning units blowing on or near the plants, it could cause low humidity at certain times, drying out the pitchers and leaves before they develop. Once a Nepenthes adapts to a particular humidity level, try to keep it within that range consistently. Some ups and downs of 5 or 10 percent will be normal over the course of a few hours as the temperature changes, but it should maintain consistently in that range, like around 45-55% in my home. If you feel that the humidity is causing problems, redirect the vents and keep the plants clustered together to hold in humidity more.

You might want to contact the experts at Sarracenia Northwest if you still need more advice as they have experience with just about every Nepenthes there is. The basics I covered should help, but there might be some detail I have not yet encountered. The white tips on the tendrils seem to point to drying or temperature changes from some source or from too little light, causing pitcher failure.

Christopher