Question
I live in southern Louisiana and now with the cool weather setting in I've moved my nepenthes indoors and placed them in two 4 tier greenhouses infront of a west window.  I have lowland neps.  I have placed a humidifier in each and have 2 T8 shop lights for additional lighting..the bulbs are listed "outdoor".  My question is how can I tell if I have enough lighting?  I've seen pictures of miranda's with beautiful colored leaves due to proper lighting...mine are green.  But all my neps seem to be doing o.k.  I will be purchasing an outdoor greenhouse in January which will be their permanent home so I am just hoping that until then I am supplying a good amount of light they need. I would like to place shop lights inside but am afraid that he humidity will blow or short out the lights.  Any suggestions are recommendations?

Answer
In this case it would be helpful to know the specific plants you're growing.  You mentioned Miranda, but I'm not clear if that's what you have or if that is what you're comparing your plants to.  Yes, Miranda will produce beautifully colored leaves in strong lighting.  It does so because of it's maxima parentage.  Other plants and hybrids don't have colorful leaves, so your plants could simply a variety that has green leaves regardless of the amount of light.  

In general, if you're satisfied with the growth of your plant and it's producing pitchers, then you can safely assume that your lighting is sufficient.  Regardless of any recommendations, your plants are always the final judge of what's sufficient.  Our recommendations are simply guidelines to get you in the ballpark.  From there, you'll need to adjust your microclimate.  

Start your lights 12 inches above your plants.  Keep the daylight hours at 12-14 hours.  After a month, assess your plants.  If you're not satisfied with the color or growth, move the lights closer, about 8 inches.  

I also recommend watching Volume 3 of the Grow Carnivorous Plants DVD series.  We show how to grow Nepenthes in your windowsill.  We also show lots of different species and hybrids so you can know what type of growth to expect from your plants.

If you need further assistance, write back with the specific types of plants you have.  Otherwise, send us a photograph and we'll help you identify them.

http://www.cobraplant.com/DVD

Good growing!
Jacob Farin