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It is common to experience episodes of contaminated cannabis when you are a grower. It is important to be aware of every part of the grow process and be able to identify anything that would cause you not to have a good yield. One of the things that could contribute to this would be contaminated cannabis plants.

Recreational cannabis is very popular these days and so is medical cannabis, but no consumer wants to buy cannabis that is contaminated. For the grower, it is important to grow healthy cannabis plants to serve the cannabis market and the consumers. We have put together several tips on how you can spot contaminated cannabis or just how you can avoid the contamination.


Contamination will depend on certain factors, depending on whether you are growing cannabis outside or inside. You can only rely on knowledge and experience to make sure that your cannabis is not contaminated. It could start with trial and error or learning more about how to detect contaminated cannabis.

The contamination of your cannabis is a common occurrence and it can take place at any point of the growth process. It can happen at harvest or when you are extracting oil. If you are storing your cannabis inside a facility, you can experience contamination, especially when you are storing the cannabis for long periods. That is when mold and mildew will attack your cannabis plants. In some cases, it is through the chemical analysis process that contaminated cannabis can be discovered.

powdery mildew on marijuana plant.


One of the causes of contaminated cannabis is the growth of fungus. When the plants get mold and mildew, it results in contamination. And so, if you notice a fuzzy texture or white powder on the leaves of your cannabis plant, then you can safely say that this is a sign of fungal infection.

To combat this problem, make sure you use a hygrometer and thermometer to keep the humidity and the temperature at the right level. Conduct frequent inspections, hunting for the sign of contaminated cannabis.


Another cause of contaminated cannabis is bacteria, which build up over time and so, it has to be quickly detected. Study has shown that bacilli can contaminate medical cannabis sold in dispensaries. Microbial tests have to be done first in order for contamination to be detected.

Solvent Residue

Some growers use the cannabis extraction process to make hash oil, tinctures, edibles and topical creams. Even though, there are many benefits to the medical community to use the extraction process, it does leave solvent residue behind in the process.

But this is only true if the process is not carried out accurately. You have to take extreme care when you are creating extraction based products or you could have contaminated cannabis products on your hand.

Pesticide Use on Marijuana: What You Need to Know

Insects and Pesticides

You should pay close attention to whether insects are troubling your cannabis grow operation. But be careful not to use spray pesticides or you could have contaminated cannabis issues to deal with. The spray pesticides might get rid of the insects, but it could damage your cannabis plants in a negative way.

Moreover, pesticides on your cannabis plant could also be detrimental to the consumer's health. There are some pesticides that stay inside the plant, even when it has been harvested and cured. If the consumer inhales this, it can cause dangerous health issues.

Final Summary

Contaminated cannabis is not good for anyone's health, but since it is a common occurrence, you have to pay close attention to the entire growth process. It is best to do a test once the crop has been harvested. Always follow local regulations with regard to permitted substances.

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Luis Cordova
Luis Cordova

Luis Cordova is a distinguished author, and renowned expert in cannabis cultivation, who possesses a Master's degree in Plant Biotechnology and Pharmaceutical Science. As a valued contributor to highly esteemed publications such as Cannabis Training University and Maximum Yield Magazine, Luis has emerged as a trusted source of guidance and knowledge in the cannabis industry. Having written thousands of informative articles, Luis is widely recognized for his comprehensive expertise on cultivating cannabis, both indoors and outdoors.

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