That kills all the bacteria. What is going to break down the worm castings, etc?
Considering the context of the original response this seems to be a contentious response. But im assuming you want a real answer, so will explain it as such. Hopefully it explains why it appears that way at face value by the time i finish. Dont take this the wrong way. Im just trying to spread more uniform knowledge then have a new beginner think only those are sterile mediums and that would be furthest thing from accurate. The goal here is to ensure people arent mislead, not in any way be negative to you or your position. So i will apologize in advance as i write this if any portion comes across that way in written context. As not my intent.
You add the good bacteria back in. Like you probably already do in the form of some commercial product. Thats probably the easiest thing to do in the entire equation. Which is the entire point of doing it. Kill it all and add the good. Thats the beauty of bacteria and fungi being asexual. Only need to inoculate it to encourage growth.
That is the difference between pasteurization(135-140F) and sterilization(180F). where pasteurization leaves some good microbes, Which is the basis for compost and its sterilization process with temps ranging from 135-170F. ***pasteurization is also known to leave nasty microbes as well and is only used on good soil where you want to eliminate the lower end of the spectrum. If you face say verticillium wilt you have to do 2+ hours at 180 degrees i believe. So pasteurization is largely a form of sterilization for healthy soil.
That is why when you sterilize you have to add the good microbes in or you create a medium for the bad to take over from seed or water contamination. If left untreated. But the goal is to sterilize to ensure all those good ones you have take over. Where the amendments can modify the microbe community composition and as a result, enhance the competition and/or antagonism among the microbes, leading to a decrease in plant pathogens activity.
This is why you sterilize then amend+plant.
In the most basic sense its as simple as just adding one or a few compost starter mixes back in and watch em go!
when speaking to sterilization and soil blends in the broad sense.
Not everything you use you want to compost before blending into the mix. Sterilization of certain mediums allows for faster mixing and usage of soil blends where you can use a sterile medium added to organic compost to go alot further(think - compost + manure blends). Foregoing the need to compost all of the medium, creating a longer working life. Helping to ensure reduced contamination, while giving one the ability to produce a healthier soil, with more nutritional value. The wrong mix of manure and you will find it will take nitrogen from your soil vs add it. Like if it has lots of bedding. Then there is the weed seeds its full of. Way too many reasons to list mainly because.....
At face value.... None of that matters in response to the phrase "Both of them are more appealing to me than dirt because the media
can be sterilized." when
they all can be sterilized. What does the microbes matter if you want to use a medium because it has no microbes? is the question i would ask. You tend to use them because they are sterilized and promote good 'microbe' growth. When all they do to sterilize coco is cook it at 180 degrees.
So the same reasons you prefer those mediums, are the same standards i apply to any and all soil. Is the most basic answer to your question.
What it sounds like you are inferring is that you prefer them(as well as most who make the argument for them) because they come already sterilized because you dont want to sterilize your soil. Since they all can be sterilized. & Most should be sterilized in the rawest most unknown form.
Hopefully that explains why you can sterilize all mediums, why its ok, why you should do it, Why one is not better than the other simply because it has been sterilized. All of those mediums have their place, but i can assure you none of the reasons they are what they are has to do with sterilization. Maybe more to the high saprophytic capacity or other things. The fact it has more ability to home good microbes than bad vs say manure. But outright sterilization for me isnt even on the pro/con list for any medium. Simply because they all can be sterilized. But one should never confuse it having been sterilized at some point as being sterilized by the time you plan to use it. Doesnt work that way. Much like if you took a syringe out of the pack and left it on a counter. It was sterilized but is no longer going to be sterile. One cant assume after that coco traveled 4000km it has remained sterile in non sterile environments. Unless you sterilized it.
Im a firm believer in if you arent doing everything sterile you can only make attempts at sterility. Which tends to be more a lie we tell ourselves then actually sterile by the standards used at the highest levels.
I actually have 2 old ovens outside i use to cook my soil for pots. Hooked em up to propane tanks and bake em all. got them free on the side of the road. I use the bottom of a 55 gallon drum i cut off and can fit about 5cu ft per oven. but when i need to do a greenhouse or more than an acre. I call in the steamer.
Im actually working with the guy now to see if we can prepare fields using steam and not having to til. So far our testing has show great results. Could be on the track of preparing fields for no til, with no tilling.
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