Feeding Nepenthes: Lessons from Nepenthes bicalcarata

Nepenthes bicalcarata

I'm a big fan of feeding Nepenthes. In a few of my growing guides, I've talked about how I fertilize my plants. My system is pretty simple and largely based off avoiding algae and fungal growth as well as maximizing impact of fertilizer. I also have to figure out how to use what I have available. My method is as follows:

• Extra Large Pitchers: Dilute MaxSea is used to fill the pitcher.
• Medium-to-Large Pitchers: A single Osmocote pellet is placed in the pitcher.
• Small-to-Medium Pitchers: Beta pellets are placed in the pitcher.

This method works fairly well. The only exception is the Osmocote. Sometimes, Osmocote pellets dump all of their fertilizer at once. This causes the pitcher to die. As a consequence, I'm looking to move to a complete dilute MaxSea method after I run out of Osmocote, which will probably be a couple more years, at least. (I try not to collect various fertilizers, if I can avoid it). Acquiring a dropper will also allow me to use MaxSea for small as well as medium pitchers, too. 

Nepenthes bicalcarata

So all is well and good, right? Not quite. A while ago I noticed that Nepenthes bicalcarata, one of the most voracious plants, according to some growers, had real difficulty with pitcher feeding. I had been placing 1 - 3 Osmocote pellets in its soil per some instructions I found online, but this invariably leaked and caused algae growth in the water tray, something I was trying to avoid. So I started pitcher feeding after doing a little experimentation.

Nepenthes bicalcarata

One thing I noticed about Nepenthes bicalcarata is that its pitchers died off at a much higher rate than other Nepenthes, even other lowland Nepenthes, when fed via the pitchers. I thought that this was unusual, but then I heard someone comment on how the pitcher fluid of Nepenthes bicalcarata was different than other species due to its mutualistic relationship with Camponotus schmitzi, a type of ant. 

In fact, Nepenthes bicalcarata is more properly considered a myrmecotroph (ant-fed plant) than a carnivorous plant because the majority of "prey" caught by Nepenthes bicalcarata is actually taken by the ant. In return, the ant's excrement and, sometimes, ant remains, feed the plant. As such, this species does not have to deal with the same kind of putrefaction of remains as other species of Nepenthes. Thus, the pH level of its pitcher fluid is less acidic and it appears to lack digestive enzymes. As a consequence, plants not inhabited by Camponotus schmitzi do not appear to benefit from catching insects.  

My thought is that Nepenthes bicalcarata is a bit more sensitive to fertilizing than other species as a consequence of its mutualistic relationship with Camponotus schmitzi. As such, I've started experimenting with feeding it less. I also intend on fertilizing its soil a bit more and see what, if any, impact that has the plant. I'll report back when I have more data.