Eli5: To grow mushrooms you need 100% cleanliness to avoid contamination, how do they grow in the wild?



I mean, if the slightest bacteria can destroy the mushrooms growth or even make them not grow at all.. how do they survive and expand in nature?

In: Earth Science

You don’t need 100% cleanliness. You can absolutely grow mushrooms even in open air. There are in fact countless open-air grow kits for things like oyster mushrooms and others.

Yes, proper sanitary practices or growing mushrooms in a somewhat contained environment will help reduce the chance something unfavorable grows. It’s by no means necessary in most cases. If you really really care about a particular batch not getting infected, sure you can spend more effort setting up a grow tub that’s mostly closed, but you still need some degree of free air exchange so bacteria’s still getting in. You’re just exposing it less.

Same deal in nature. For the most part, it’s fine. If not, then they’ll have a hard time growing or the entire substrate will be infected and they’ll just not grow. Nature’s fairly brutal like that.

It’s really easy to grow mushrooms..the reason everything needs to be sterile is so only the stuff you want to grow grows. Don’t want your mushrooms contaminated with other harmful fungi

I think the problem is that you’re creating an absolutely ideal environment for fungi to grow, which is unfortunately also an ideal environment for many molds and bacteria as well as competing fungi.

So, it’s a race between the preferred fungi and these less ideal alternatives because once the good fungi establishes itself, it’s immune system should be able to combat potential hazards. However, if you’re raising fungi for human consumption, even a small amount of infection by a foreign bacteria or mold could render the entire crop inedible

Mushrooms and fungi can grow in many different environments, and they also produce millions of spores so they have very good chances of at least one of them being able to colonize an area. When people grow mushrooms artificially in mycoculture, they generally want to maximize the number of spores that colonize the substrate. We also generally harvest the mushrooms, which are the “fruiting body” of the mycelium, or cobwebby looking filaments that the fungus spends most of it’s time growing. This means that the mushroom you grow has less time to put spores into the environment because you harvest it instead of letting it decompose like it would in nature. You don’t necessarily need a sterile environment to grow mushrooms, but keeping your growing medium (sawdust, rice flour, etc) sterile can help reduce the amount of contamination and give you a better success rate. Mold and yeasts are also fungi, and are very opportunistic and can quickly spread into a suitable substrate, usually faster than a mushroom mycelium can colonize it. Sterilization simply improves your chances of growing the type of fungus you want, rather than random molds or yeasts which usually exist in the form of floating airborne spores.