Carnivorous Plants/Discolored leaves on a Nepenthes
Thanks for your note. I'll try to send you a photo if I find a way to hold the terrarium up to my iMac's built-in digital camera. Meanwhile, the cookie-jar-like terrarium stands about a foot away from the 48-Watt grow light. I don't know what kind of soil(?) is in there because a nursery employee built the terrarium for me and told me not to water it because it would water itself. I do know that the Nep. seemed heathy before winter came here in Schcenectady, New York. So temperature change and sporadic lighting are the only potential potential problems I know of. In fact, I wonder whether the plant is getting too much light because the healthiest-looking leaf is farthest from the lightbulb.
I'm sorry I don't know the species name of any plant in the terrarium. But the Nepenthes shares the terrarium with four healthy-looking plants: two Droseras, at least one of which grew from seed, a Pingguicula, and some kind of weed-like non-carnivorous plant that I noticed recently because part of it popped out when I uncovered the terrarium. I haven't sown any seeds in there.
I hope I haven't harmed the poor plant to severely. Unfortunately, I'm only a beginning CP-grower. God willing, my Dionea muscipulas will be all right when they leave the refrigerator on February 20th.
Is your nursery employee doing the maintenance on the terrarium? You won't need to add much water (maybe a little once a month), but they do loose some water over time, especially if it's being opened at all to feed plants. You also have to be on the watch for mold growth which can be deadly in an enclosed environment.
If you're light is a foot away, you may be getting some darkening on the leaves, but that may be normal depending on the species of Nepenthes. Many have darker leaves when growing in normal sunny conditions.
Are your plants anywhere near a window? You mentioned a change in appearance in winter.
You mentioned you have some Venus Flytraps in the refrigerator. Be sure and check those once is awhile to make sure they don't have any mold growing on them. If they haven't been sprayed with a fungicide, it's a good idea to do so since it's so easy for them to get moldy in a cold, dark fridge. Safer brand sulfur-based fungicide available at most garden centers works very well, and is very low tox.
When you take them out of the refrigerator for their dormancy, they will be happiest growing as outdoor container plants for the late spring and summer. Venus flytraps are actually zone #8 perennials. Ours here in Western Oregon stay outside all year. We have a good customer in Syracuse, NY that has a beautiful bog garden with many Sarracenia, Flytraps and North American Sundews that she heavily mulches in winter, then uncovers in the spring. The plants come back in the spring every year. In their native North Carolina, temperatures in the 20's are not uncommon during the winter.
Looking forward to seeing your terrarium photos.