Carnivorous Plants/insecticide


Hello! Lately I've been seeing fungus gnats in the soil from the pots of my nepenthes. I bought an insecticide who's main ingredients are pyrethrins and piperonyl butoxide. I watched your video on insecticides and I know that pyrethrins are safe to use. Is this insecticide still safe to use on my nepenthes if it has piperonyl butoxide in it?

Hi Victor,

Most formulations with Pyrethrins contain Piperonyl butoxide, and it is a synergist that helps the Pyrethrins be more effective.  It is totally safe on the plants.

Another, lower toxicity way to kill fungus gnats is to use BTI dunks or granules in your water for the plants.  BTI spores are very specific to fly/mosquito species and kill the larvae.  It is completely harmless to other insects and animals.  We use BTI mosquito dunks routinely in the summer in our Sarracenia pools, and in our Nepenthes house during the winter.  For just a few plants you could just keep a watering can with a dunk in it, then water your Nepenthes with it.  The Fungus gnats should disappear in about two weeks.  You can use sundews or sticky traps to catch the adult insects.  Here's an example of this product:

Good Growing!

Jeff Dallas
Sarracenia Northwest

Carnivorous Plants

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Sarracenia Northwest


If your carnivorous plant is showing poor growth, discoloration, abnormal leaves or possible infestation, the expert growers at Sarracenia Northwest can help! They have a great depth of experience dealing with diseases, pathogens, and abnormal growth in carnivorous plants.

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