Question
Hi, I will be growing my carnivorous plants indoors, so I have a question about the light. I've got a couple of 40 watt florescent tubes, but the only description I see on them is Daylight instead of cool or warm white. I understand Daylight are older tubes. Will these work for the plants? They will be placed in groups of four. Also where I live the humidity is very low, from 10 to 40. From what I've read this is to low, so what can I do to increase the humidity in the room. I will be growing fly traps, various pitchers (not tropical) and sundews. Thanx

Answer
Hi Johan,

Daylight tubes are fine.  They tend to be a bit more towards the blue end of the spectrum, but plants photosynthesize in the range anyway.  Using 4 tubes is great.

Now I'm going to rant a bit.  Most of what you read about the humidity requirements of carnivorous plants is somewhere between a grain of truth, to absolute fiction.  We spend a great deal of time in our nursery dispelling this myth, yet it seems to have the tenacity of religious cult doctrine.  As with anything there are exceptions such as lowland Nepenthes, and Woolly Sundews, but far more don't need it than do.  Here's a quote from an author that got me headed the right direction on growing cp many years ago:  "There is still far too much folklore concerning the humidity requirements of carnivorous plants.  We are repeatedly informed that if cultivation is to be attempted humidity must be at its highest, and that the plants are best confined to a glass or plastic case.  In most cases, the use of such a cover is not only unnecessary but harmful.  The lack of air movement, combined with high humidity, can encourage fungal attack, cut the light level due to condensation, and prevents entry of prey."--Adrian Slack, "Insect Eating Plants and How to Grow Them".

Once you have your lights set up, the ambient humidity created by the water in the soil of the pots, and from your water trays tends to create a great little microclimate.  We have grown plants like this for decades with great results.  Just make sure your plants are within about 3 inches of the tubes.

Now, let's talk plant selection.  I would highly encourage you to consider growing tropicals under your lights such as Nepenthes, tropical sundews, Mexican butterworts, etc...  I would highly discourage you from growing temperate perennial (winter hardy) plants such as Venus flytraps, Sarracenia pitcher plants and hardy sundews under your lights.  The tropical plants are used to temperature conditions year-round that you'll be creating under your lights.  The temperate plants are used to hot summers and cool to cold winters, and need their dormancy in the winter.  Plants such as Venus flytraps will do ok for about a year under lights, but if deprived of their dormancy, they die after about a year.  Same with temperate sundews.  Sarracenia can fare a bit better, but you can only grow short species such as S. purpurea venosa or S. psittacina under fluorescent lights.  Trumpet pitcher varieties such as S. flava would have to be under HID lights.  They are full sun plants needing about the same light levels as tomato or corn plants.

When you get a chance, visit our caresheet pages:  http://cobraplant.com/index.php?main_page=page&id=7&chapter=1&zenid=20a4af31fa01...
You'll find lots of information here on specifics of different species.  Also consider taking a look at our e-book.  http://cobraplant.com/index.php?main_page=index&cPath=1
We go into much detail about these common pitfall issues, and much more.


Good Growing!

Jeff Dallas
Sarracenia Northwest
http://www.cobraplant.com