hi everyone, I got a question about sterilizing soil, I inherited some greenfield roots organic soil. (10 bags- (1.5 cubic Ft). and I’m afraid it may be loaded with bad bugs, as the room witch they came from was loaded with fungus gnats\white flies. so i was thinking of sterilizing the soil. was told this soil would take me through veg with out nutes, what will happen when i sterilize. will i need to re-amend. would hate too throw out that much soil.
Thanks krusty.
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How are you going to sterlize? In the oven? that shouldn’t change anything you shouldn’t have to re-amend IMO. I used to sterilize in the oven, it worked great. I find it easier to user Gnatrol now.
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If you sterilize them in the oven it bakes all the microbes 
so you will have later on to repopulate the beneficial ones with some tea or specific product so they could help feeding the plant … 
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Mule skiner: Yes, it will be done in oven. Are there other options?Any instruction
IE Temps & time? George1961: could i use Something like cal- mag., any advice would greatly be appreciated
Thanks krusty62
I use a microwave. A small one. OUTSIDE (it smells)
It’s 800 watts and I cook my home made compost for 18 mins.
I use it in my mix for seedlings and indoor growing
I reintroduce various microbes when appropriate
Soil is not " sterilized " but I am not buying an autoclave.
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here are a couple articles, it looks like 180 degrees and 30 minutes in the oven. Beware the whole house will smell like a peat fire and the oven will smell like burning peat the next few times you use it after this.
For smaller amounts of soil I’ve had good luck putting it in a container outside and pouring boiling water through. I never noticed any harm from the dropoff in soil microbes although it must have happened.
https://homeguides.sfgate.com/sterilize-used-potting-soil-35823.html
https://seasonalpreferences.com/sterilize-potting-soil/
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There are many ways to sterility, dry or steam/pressure heat. UV, chemicals, gases, radio frequency etc.
For dry method
180°C for at least 2 hours
Or
250°C for 30min to 1 hour.
To steam sterilise in a pressure cooker
120°C for 30 min at 1 bar
The articles temperatures and times are way off, at best they pasteurize, not sterilise.
Hope this helps.
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Nutrient content won’t change much. 15cuft is one hell of a batch to sterilize.
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Exactly… Either a big oven or a huge pressure cooker!!
Or use a old oil drum and adapt like some people for mushroom cultivation.
I’m a bottles man, no organics, but here you can find useful info … 
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RR Roger Rabbit, some.of you might know from other forums dedicated to mushroom farming.
Mushroom mountain oil drum tech
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oven to 180 degrees thru out for 60 minutes. (they say 30)
or Ozone. That has been my go to lately for sterilizing dirt. (has to be stirred up)
The info on the site isn’t the most accurate. And it should be 180° Celsius not Fahrenheit. Big difference. But that’s why I was saying that they got the info wrong. They telling one to sterile when it’s pasteurization
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Thanks everyone, it’s 1.5 x 10.
Got a lot to think about, probably gonna do a small trial run. In separate room with pest control
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I should have more clear also. Get the heat of the dirt to 180 (and i meant F), and hold it there for 60 minutes. I used to use 350 in the oven to get it there. But now, I have an ozone generator I use. Like it far better.
Fahrenheit bo Celsius in this case → 180f is 83°C in this case it’s a pasteurization, ideally it should be 200f approx 85°C. I guess in this case it’s enough to cook the eggs, insects, nemotods and so on. But most bacteria won’t die, only the pathogen ones (for us that is). Sterility includes a much wider scope of thermophile bacteria and also viruses. Plus many bacteria will sporulate (a latent form) and don’t get destroyed hence the higher temps.
But if the ozone works, cool 
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It’s not sterilization because you don’t want sterilization - the OP said he wanted to kill fungus gnats. Most insects die at much lower temperatures than true sterilization. For example beg bugs die at 113 degrees F. I think getting the soil to 140 degrees F is more than enough to wipe out gnat larvae.
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I microwave my soil in small batches for 2 to 3 min at a time.
Could you give me a little knowledge about ozone generator, I need to clean over 15 cubic ft. Don’t think oven is way too go
The topic does say “Sterilizing soil”.
I was just informing and alerting to the inaccuracie of the article that’s all.
One thing is sterile and another is pasteurized.
Anyway. I hope it helped. Not trying to diss anyone. Only the article.
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