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Solar ovens are handy for sterilizing organic fertilizer mixes in relatively small quantities. The simplest version is just a box lined with black absorbant material (not plastic, it might melt) with a glass plate on top, and orient towards the sun around noon for a few hours. Test it for sufficient heat generation for sterilization purposes by seeing if a metal cup full of water starts boiling.

Even then you should wear an decent mask when handling all fertilizers, you don't want to be breathing the dust regardless of whether it's synthetic or organic fertilizer.






Solar ovens will absolutely NOT sterilize fertilizers. They _do_ kill most of e.coli and listeria bacteria, but plenty of bacterial spores will survive. It also will generate dust, that can be deadly.

Instead, you should keep the fertilizer in a heap under some straw. This lets a mosty-non-pathogenic microflora to get established and eat pathogenic bacteria.


You have no idea what sterilization means.

For 'moist' heat, temperatures of approximately 121–129 °C with pressure are used, whereas 'dry' heat requires temperatures from 176 to 232 °C for longer duration.


How can this be the case if for something far more direct-to-the-gut like cooking, the process of heating your food to about 75°C for at least a few seconds is enough to kill every known pathogen (except maybe prions, not sure about them).

Given that, why would you need 121°C, let alone 232°C to sterilize things like compost?

I know that high temperatures don't destroy all known microbe-created toxins, but then, that's not the definition of sterilization, which is about simply destroying the pathogens themselves.


https://en.m.wikipedia.org/wiki/Sterilization_(microbiology)

Cooking reduces pathogens to a “safe” level. Sterilization is meant to overkill and eradicate them.


"How can this be the case if for something far more direct-to-the-gut like cooking, the process of heating your food to about 75°C for at least a few seconds is enough to kill every known pathogen (except maybe prions, not sure about them)."

Microorganisms are more stable than you think. Yes, 75 degree celsius kills some of them, but it is a log function. A few seconds won't help you that much.

And then there are some real bad ones that don't mind being boiled: https://en.wikipedia.org/wiki/Endospore

And we are not talking yet about extremophile organisms. The endospores will survive boiling water. Extremophiles can grow above 100 degree celsius. Obviously we are talking here deep sea level so that a hot spring can have over 100 degree without going to the gas phase. But these extremophiles are unlikely to be found in your kitchen.


“Fun” fact: prions can survive an autoclave!

Cooking isn't sterilization (but maybe you don't need sterilization).

To those of you who replied in good faith with explanations for an honest doubt I had about sterilization, I thank you. Details to keep in mind when cooking, or composting.

To those who downvoted my honest question about the temperature mechanics of sterilization of chemical substances (food and compost both being examples of such), Thank you for being the kinds of silly, pedantic neckbeards who give this website's comment threats a bad name on other parts of the internet.


Won't kill all spores, so no.



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