There are different sources of contamination, and these can be placed into three categories, which are pests, bacteria, and mold. In this article, we’ll take you through some tips to help you identify a contaminated magic mushroom culture. You’ll also learn about the common types of contaminants to know.

It’s not always easy to cultivate mushrooms at home, but it’s also not rocket science. However, the most important thing about the whole process is to ensure that you’re careful and that the process is entirely clean. This is because the environmental condition for the growth of mushrooms should always be sterile. All the parts of the mushroom culture are vulnerable to contamination, and this includes the mycelium, the spores, and the fruiting body.

The common ways of keeping the environment rich and sterile for the mycelium include air filtration and substrate sterilization. This is also an effective way to keep the mycelium free of competitors like pests, bacteria, and molds. However, a key thing to always have in mind is that the sterile environment is momentary, and you’ll need to constantly maintain it.

What is a Contamination?

Contamination is simply anything you don’t want in your mycelium or substrate, including air, water, or soil impurities that can cause problems in your magic mushroom culture. Spore contamination can be fatal for the entire culture, and contamination during the fruiting growth phase can cause cap removal. The spread of contamination is very quick, which is why it’s best to eliminate contaminated magic mushroom cultures immediately.

Fortunately, contaminants are easy to identify because the mycelium is mostly white. Therefore, if you observe other colors, you’ll know that the culture has been contaminated. However, you don’t need to be hasty because there are two exceptions. Yellow is an indication that the mycelium is old and offers defenses against bacteria, while blue is an indication of bruising on the mycelium surface.

Types of Contaminations

Contaminants can flourish in a sterilized substrate for mushroom cultivation, and this is not because they don’t have a competition, unlike when in nature. When in the wild, there’s an ecological equilibrium that allows the mushroom to grow freely, irrespective of the presence of different bacteria and other fungi. This is also without the need to fight for substrate dominance with contaminants.

Basically, there are different contaminations out there, and as mentioned earlier, they can be grouped into pests, bacteria, and fungi. Pests include tiny insects that feed on the culture and also transmit diseases that can affect its growth. With strict sanitation, you can easily control pests. Bacteria are microorganisms with a fast reproductive rate, but they can be dealt with through substrate sterilization and pasteurization. Finally, mold is a fungus that grows in filaments called hyphae. They can easily be controlled with the aid of alcohol, cinnamon, baking soda, and salt.

First Phase of Contamination

Seeing that you have a contaminated magic mushroom culture can be disheartening, but it’s, but it’s crucial that you know the signs to look out for and how to act quickly. Also note that the fact that a fruiting box or culture falls victim to contamination is not an indication that the entire system has been compromised.

One of the most noticeable signs to look out for is signs of discoloration. Invasive molds usually have bright and distinct colors. Therefore, if you sport black, grey, blue, or green patches, it could be an indication that your culture is contaminated. In some cases, blue stains may only be an indication of bruising and not a contamination.

Another thing worth noting is that fungi species are not the only contaminant that can inhabit your substrate. Bacteria is also a major source of contamination, and this is evident by the presence of slime. Slimy patches on mycelium or grain are an indication of excess moisture, and this could also be a potential sign of bacterial contamination.

The sad thing about contaminants is that some invasive fungi are not always easy to identify. This is because their appearance and color usually blend with that of the cultivated mycelium. However, with a very close inspection, you can easily tell their differences. Another set of intruders you should note are sporophores, and you can use a microscope to scan for them. They usually look like hair-like structures. Other signs of contamination include dusty texture and the presence of substances that looks like a powder on the surface of the mycelium.

Common Examples of Mushroom Kit Contaminations

With everything above, you now know the different types of contaminations in mushrooms and how you can easily identify them. Let us now look at some of the most common examples of mushroom kit contamination.


They are usually common in manure and straw. Some species of mites offer benefits for the growth of mushrooms because they feed on other mites and eelworms. They are also vital for mixing and the fragmentation of the substrate. Despite that, it’s worth noting that there are some species that can cause damage. This is because they usually feed on the mycelium, and this can cause discoloration. With detailed sanitation and proper maintenance of hygiene, you can handle this type of contamination.

Fungus Gnats

These are tiny flying insects that are mostly attracted to the mushroom crop. They tunnel into the mushrooms and feed on the mycelium, and the damaged mushroom tissues attract other contaminants like bacteria, which can cause them to rot. This type of contamination can also be prevented by strict sanitation and maintenance of hygiene.

Dry Bubble

This is a condition that is caused by Verticillium fungi species, and it produces sticky spores. The symptom of the condition depends on the developmental stage. The earlier stage of infection causes the production of deformed pinheads, while infections at the later stages cause the production of crooked mushrooms with caps that are tilted. The pores are mostly spread with dust particles because they are sticky. With that, it’s important to be careful with moving soil around your house.

Black Mold

This is a common fungus found in grain and agar, as well as other organic substrates. They are also known as Aspergillus, and they generally prefer conditions with neutral to slightly basic pH. It’s important to note that some species of this organism are toxic because they produce harmful aflatoxins. Therefore, they should be handled with extra care.

Pink Mold / Red Bread Mold

This type of mold is known as Neurospora, and it grows at a fast rate on grain and agar culture. The contaminant is abundant in nature, and it can grow through filter discs and cotton stoppers, making it difficult to eliminate. It’s advisable to destroy contaminated cultures immediately, and this should also include a thorough cleaning of the environment.

Green Mold

This is caused by Trichoderma harzianum, which is characterized by its unique white and aggressive mycelium that covers the entire mushroom. It also causes the mushroom to rot and produce emerald spores. The use of disinfectants and proper sanitation is essential to prevent this contamination.

Bacterial Blotch

If you notice brown to yellow lesions on your mushroom caps, it’s a sign that your culture is contaminated with bacterial blotch. The bacteria are usually spread by soil particles, and this becomes severe when the mushroom stays in a moist environment for up six hours after they are watered. To control this, you only need to lower humidity and apply 150ppm chlorine solution.


These are the most common magic mushroom contaminants, and we have highlighted the so you can easily identify contaminated magic mushroom cultures. The most important thing to always remember is to always maintain a clean environment and handle mushrooms with extra care so they don’t get contaminated. Ultimately, if you’re looking to buy uncontaminated magic mushrooms, magic truffles, grow kits, and other mushroom supplements, we recommend checking Microdose Bros online store now.