Question
The Nepenthes I purchased from you last fall has almost doubled in size. The lower older leaves have turned brown and I removed them. My question is the tiny pitchers on the new bright green leaves never develop to any size and appear to remain closed.

The plant is hanging in a west window with slightly filtered and indirect sunlight. It is only watered with rain water. Since it has not outgrown its small shipping container I have not transplanted it. Also the leaves have started growing bigger since spring has arrived here in NC.

Do I need to do something different for the pitchers to fully develop?

Answer
Hi Ken,

Typically the lack of pitchers is caused by a lack of sufficient sunlight and/or lack of sufficient humidity.  Being in North Carolina, humidity wouldn't be a concern unless you have the plant near a heat vent or AC.  

You mentioned about giving your plant slightly filtered and indirect sunlight.  If the leaves are bright green and large, then they could use more sun.  Increase the light intensity so that it receives a few hours of direct sun and very bright filtered light during the rest of the day.  With more sunlight, you will see smaller leaves with a tinge of yellow.  You should also repot the plant in a larger pot to make sure the pot is retaining sufficient moisture.

In late spring, you could move your plant outdoors, such as under a tree where it can get dappled sunlight throughout the day.  We do that here at our nursery, and our ventricosa explodes with pitchers!

For more information about growing Nepenthes, watch Volume 3 of the Grow Carnivorous Plants DVD series.
http://www.cobraplant.com/DVD

Good growing!
Jacob Farin