Just wondering how would everyone go about reusing outdoor soil indoors? How does one sterilize the soil per say?
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Steaming. But the process sucks unless you invest into it which was a major “why bother when I have a backyard to use this stuff” moment.
In theory (because I’ve never done it), you could get a janky large pot and fill it with soil and just enough water for it to generate and hold in the steam for about 30min to kill anything in there.
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At one point I was considering a DIY solar oven but the situation changed and didn’t go that route.
Cheers
G
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Are you growing organic? If not you could put that into a oven to warm it and kill any life. But that would be expensive for so much soil. Or put on top of a fire to cook slowly for some time for a cheaper version.
If you’re into organics, you’d have to reamend the soil, let it cook, and probably add a bunch of predators depending on the pests you think may be in there.
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If your going to sterilize with steam it takes roughly 90 minutes at 15psi in a pressure cooker to sterilize CocoaCoir for mushroom cultivation, so I would give it a lot longer. Personally I never bother to sterilize my re used soil for weed growing. I just add neam meal to the soil mix to help combat anything bug related.
As funk junky says you can re ammendment with some high nitrogen mulch and it will cook on its own and kill off any unwanted things.
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Treat it with LABS, compost tea, microbial supplements mix it with fresh compost/worm castings, maybe some extra pumice. keep it moist for a month, turning regularly. And it’s good to go.
The only way I would pasteurize soil is if it is currently known to be infested or infected.
The “wanted” things that you add will balance the soil web.
I’ve been reusing soil stored in a couple of sterilite bins for over a year now; it just sits open outside under the carport until I’m ready to add it to a pot.
Sterile soil is BAD, which is why we pasteurize instead of sterilize. Sterile soil is very prone to infection and contamination, because there are no resident microbes to maintain balance.
If you need to kill known organisms in the soil, wet it down pile it in a container so it’s about 12-16 inches deep, put a clear plastic sheet over it (in direct contact with the soil surface; I put rocks and such on the top), and put it in the sun for 3 weeks. You can look this up, it’s called solarizing. I would recommend re-seeding a microbial colony after this process.
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Look up soil solarization. If you have the time and plan ahead you might be able to make that work for you.
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Ok folks I really appreciate the feedback. I grow in salts so I’m not particularly concerned with losing any microbes . I think I’ll take a chance and use it in my next indoor run and see what happens. 
I just hate throwing out perfectly good promix lol. The soil isn’t infected that I know of
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I think headybear recommending a proper suggestion for sure. I reamend with a cup of Dr earth per 10 gallon and throw it all in 4x4 wooden crate to sit and cook till spring occasionally watering it to keep microbes active and healthy. Main thing is just having that soil exposed to direct sunlight for 8-12 hours a day, that should keep things pasteurized properly and get u geared up for next year
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Just seen ur a salt grower, def flush the fuck out of the medium, wait 15-20 min to let remaining salts dissolve and blast it again. Ur bigger concern on a reuse is excess salt build ups in my opinion so a good flush out and should be good
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As a general rule, if soil has been outdoors, it stays outdoors.
My outdoor soil undoubtedly has mold/mildew spores as well as insect eggs. Some insects are harmful and some are beneficial, so I let them duke it out.
Why not just keep your soil moist over the winter then use it again next year?
You’ll get the best results with a 50/50 mix of old & new soil.
It will have organic matter from the digested roots, plus an established microbiome. Promix on steroids!
Good luck!
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Yeah this is it, I do the same pretty much to the letter except I add the green trimmings from harvesting too, and usually some molasses water and a handful of rice or oats to get the carbs a crackin and fungal life happy
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An easier method than steaming with a pressure cooker would be pasteurization. I use this technique when making mushroom substrate. Place soil into container with a lid. I use a five gallon bucket. Boil enough water to saturate soil to desired moisture content. Pour boiling water over soil and put lid on. Let sit for 8 hours and you have pasteurized substrate.
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No
Just forget it, a bag of FFhF is 15 bucks.
Plain soil is not going to work well
If you have to amend it what’s the point?
As to sterilization
I do it to all new dirt.
Just fill a pot, I use fabric
With your soil and boil a big pot of water and pour that over your soil.
Make sure you use enough water for whatever amount of dirt you using.
Then just add per directions
Alaska fish emulsions to restock
The bacteria in the soil.
Your done.
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Pretty nice and easy instructions there, thanks…
K+
I’m always for re-amending and re-using soil but my outdoor soil stays outdoors.
I have separate tub outside and inside of each.
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Not the most practical solution, but assuming someone has access to an autoclave…would that be the best route?
I never bring outdoor soil in also I only run about 700 -800 then during later flower, I taper it down even more that’s just me. I’m not saying it’s the only way to grow with salt. It’s just a system that is worked for me and I have pretty much perfected and if I come across a plant that doesn’t like my feed. I just get rid of it. I don’t waste time with plants that are finicky