Q/A #147 - Nepenthes in Terrarium Not Producing Pitchers

QUESTION:
My Nepenthes isn’t growing pitchers.. it looks like it has three different buds that want to grow but haven’t changed in weeks. I have it in a terrarium for humidity because I live in Arizona. It sits in front of a northeast facing window with bright indirect morning light until about noon. All I have are NE facing windows though. 

I use “pitcher plant potting soil” I bought from Dirtco on Amazon. And I have a sphagnum moss layer on top. I use tap water with a mister. 

When I first got my plant about 5 months ago he had a few pitchers that I fed with a carnivorous plant feeding supplement and applied a few drops to each pitcher every other week or so but the pitchers have since died off. 

My plant has been in the same terrarium in the same spot since I got it. I did have some Venus fly traps in there that have died off. This is the only one hanging on. Right now I have some succulent cuttings in there to start off that I’ve been transplanting to other pots, Is that bad? Should I get a grow light for him? I also have a humidity meter and try to keep humidity 60-80%. I just don’t know what to do to boost these little buds into pitchers. 
( Submitted in August 2021.)

RESPONSE BY JEFF DALLAS:
OK, you're new to growing carnivorous plants, and I feel that I may be starting from scratch here, which goes beyond the scope of this format. So what I would like you to do is go to a couple of our resource pages and familiarize yourself with some information on Nepenthes. After you have reviewed this information, feel free to return here or just reply to this email with any additional questions. 

• General Nepenthes Care
• Grow Carnivorous Plants, Volume 3

With that said, here area few things that may not be in the links I provided.

First, avoid the fertilizer until your plant is back on track producing pitchers again. Also, what is the analysis of that fertilizer? I went to Amazon to take a look at it, and they don't give the ingredients. Right off, that makes me suspect of this stuff. In general, the rule with fertilizing carnivorous plants is when in doubt, don't. Many carnivores are very sensitive to fertilizer. (That's why they catch insects.) Just read all the reviews on Amazon of people that killed their Venus Flytraps with this stuff. 

Secondly, even in Arizona, humidity is a total red herring. Your plant shouldn't be in the Wardian case, but in a regular pot with drain holes. Inside a terrarium like this the plant has poor air circulation, not enough sun, and no soil drainage. Nepenthes and many tropical carnivorous plants will adapt to low humidity. 

Thirdly, the basic reason that your Nepenthes isn't producing pitchers is that it needs more sun. If your plant isn't getting enough sunlight, it won't produce pitchers, regardless of how "optimal" the humidity is. On the flip side, when a Nepenthes is grown in optimal lighting, it will produce pitchers regardless of the humidity. Read our general care guide for examples. (Your flytrap died likely because of lack of sunlight, which is one of the 5 most common mistakes with Venus flytraps.) If you need to supplement with artificial lights, watch our video about LED lights.

Finally, I recommend transplanting your Nepenthes in a different soil media. Use a mix of equal parts long-fiber sphagnum moss with perlite. It's similar to some orchid mixes. The mix you're using from Dirtco is good for bog species of carnivorous plants, such as Sarracenia and Flytraps, but not for Nepenthes. I've written to try and get this producer to change their labeling. You're not the first person that has written to me with problems with a Nepenthes after using this exact soil from Dirtco.

Pretty sure the Nepenthes you have is Nepenthes DeRoose Alata. It's a very common variety sold at a lot of garden centers. It's a super easy plant to grow as a houseplant in sunny windows. No terrarium required!

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