CO2 to kill mites

If I turn up the CO2 to 1,500-2,000 ppm, will it suffocate the spider mites and kill them? If it won’t, what will?

Carbon dioxide (CO2) is used by plants as an ingredient for photosynthesis. Plants combine it with water using light as energy. The result is sugar, which is used to supply the plant with building material and energy. Normally, CO2 is found in the air at rates of 350-400 parts per million (PPM) and climbing. When plants are given bright light they photosynthesize faster in the presence of air enriched with CO2. A typical level for bright rooms is 1,500-2,000 ppm.

CO2 is not a poison gas. We breathe it in every time we inhale and we breathe out a lot more of it when we exhale. When gardeners visit their CO2 enriched gardens they breathe levels five to six times greater than normal.

Mites breathe oxygen. If the CO2 were turned up a lot higher the mites would be able to breathe as long as there was adequate oxygen in the air. If they were placed in an all-CO2 environment where they received no oxygen for a few hours they would probably “hibernate” in some way. They would have enough of a survival rate to continue hassling your plants.

Oxygen-free environments have been used for grain storage with mixed results. They are much more effective in controlling rodents than insects.

There are a lot of approaches to eliminating mites. You can use registered organic pesticides such as Cinnamite, neem oil or other neem oil-based or organic miticides.


Releasing a full container of carbon dioxide into a sealed grow set-up will kill all mites and insects. But, don’t be in the room while the CO2 is being released! It would be enough to KILL YOU! I have seen this technique of bringing the CO2 to 10,000 ppm for 15 minutes to kill all pests. You must vent out the CO2 before entering the room. Two applications, five days apart, will kill all mites, pests and their offspring. ? Marc

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