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Using deep-freezer to sterilize soil - is it possible?

I've recently had a infestation of thrips, but luckily they seem to be gone now. This little incident got me thinking that maybe it would be a good idea to sterilize the soil im using(im growing indoor) to avoid the further presence of multi-legged bastards in my grow-room. It seems to common knowledge, that one can use an oven to do the job, but currently I only have quite a wee oven, so doing it that way would be quite labour intensive(and nobody likes work, right? ;) )
What I do have though, is a decent sized deep-freezer , so I've thought that maybe throwing the soil into the freezer at -18 degrees celsius for a while might do the job as well?

So the question in its essence: is it possible with that kind of temperature, and for how long should I leave it in there?

thanks for your help.
 

Dr Dog

Sharks have a week dedicated to me
Veteran
Well look at it this way
The insects do just fine year after year living or hibernating in those temps all year, so I dont see how it would work. Once your soil comes back to a regular temp, the thrips would just come back to life

I used to work at a ski hill, when we first opened up, there would be flies all over the window sill. You would think they were dead, but once the heat hit them, they would reanimate and you would start to wonder, how these flies survived, a good -20 to -30 for a few months.
 
Thats more or less what I thought myself. Though I thought with the relative low and constant temperature of a deep-freezer it might be possible. But I definately see your point.
 

belfast

Active member
NO.

NO.

Throw it out and make a new mix.

Here is a simple example of a Soilless mix:

50% Perlite
50% Vermiculite

or

40% Worm Castings
30% Vermiculite
30% Perlite

or
40% Peat
30% Vermiculite
30% Perlite
 
belfast:

thanks for the reply. I was thinking about sterilizing soild in general, rather than using the soil the plants with thrips were grown in. Basically I was looking for a way to minimize the chances of getting an infestation(of any kind of bugs really) from store-bought soil.
But the consensus seems clear: it won't work. So I think im just going to stuff some more veggies into the deep-freezer instead ;)
thanks for your help.
 
G

Guest

its easier to trap the perpetrator than to prevent it. I tried to ask a way to keep mites out, pretty much got laughed at. Get some stickies and don't buy MG soil. I use both Sta-Green potting mix with no bugs and some expert gardener peat from the local stores. Not even in my black kow manure compost, no bugs. Open up some MG organic/moisture control and thats a completely different story. Get the sticky pest strips. Not the kind that hang out like a yo-yo, the kind that could trap a 5 pound rat if it stepped on it.
C443.jpg

^not this kind
HouseglueE.jpg

^this kind.

Cut the peices into 1 inche strips, you can get about 8-10 out of one of those boards. They are like 3 dollers for 3 so its gonna last about a year for 3 dollers. This won't always keep everything out, but it does a really good job in the prevention department. Remember, its just as easy for a bug to infest your soil as it is to already be in it. Don't be scared, it held me back for a long time because there was no decent soil around where I lived, I made my own though and its working perfectly.
 

libby

Member
Just a thought, not foolproof, stand the bag of soil up, on end, split the top, pour plenty HOT water in, with no drain holes, then cut holes 10 mins later, cook'em,.
 
Y

YwouldntI

yo excel-then what do you do with the strips?put them in the bucket or just scatter them around the floor?or what?thanks bro
 
G

Guest


Sadly, laying on the ground is my method when I'm lazy. I usually start off under the floro tubes with 10-20 of those hanging and they selectively are taken down as they all stick onto my arm hair. The easiest way is to attatch a paperclip to it, but you have to watch the paper getting soft from getting wet(like in this pic). I put them on the herb plants like this but reverse them. Its best to put tiny ones everywhere, they were recomended to me in a THC seeds video on google or youtube. Its the one with the big guy and about 10000 clones.

3:15 in:
http://youtube.com/watch?v=Xi-kbDzYY6c&feature=related
^these two guys look like some dudes who shouldn't be incharge of 1000w lights.

A tip I have about the stickies is use a strong wire or paperclip; then you can bend them everywhich way. Also make sure you secure it through the non-sticky part, then peel off the paper. Those things stick to anything like you wouldn't believe. When you get some stuck, alcohol takes it down I believe; soap is pointless.
 
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inflorescence

Active member
Veteran
You need to invest in a pressure cooker.
All-American makes nice ones.
Nothing, bacteria, fungal spores, etc, can withstand a pressure cooker.
It's like an autoclave, to sterilize dental instruments.
It'll be time consuming but are you really growing THAT much? lol

BTW never pressure cook soiless mediums with time released capsule fert included like osmocoate, nutricote, etc.
Most time released ferts are HEAT activated, not Water actvated and your insuing sterile medium will be ridiculously high in PPM.
 
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thanks for the replies everyone.

excelAtIt: It's always funny when events coincide; just before reading your post I actually ordered some pest-strips, not the brand you refered to(i'm in europe, so I suppose most of the brands avaible in the US won't be availabale here) but something similiar. I like the idea about cutting the boards up into smaller pieces to get more spacial covering per pack. My problem regarding the soil is, that I really can't get my hands on any that have been sterilized from any nearby shops. I usually use soil of a good quality, but i suppose it was just a case of bad luck getting soil with pests in it. But I think were on to the same vibe here - preventing the pests in becoming a problem.

Libby: Thanks for the advice, but I think were moving into some uncharted waters here; a hybrid between hydroponics and soil-growing :D - plus i think the temperature have to be higher than the 100 degrees C of boiling water if you wish to sterialize the soil.

Inflorescence:
I absolutely love the idea about the preasure cooker, but right now that is a piece of equipment I really can't afford, and neither do I have space for any more misc. grow gadgets. But the idea is really good I suppose; hope it can be of help to somebody else.
Regarding being lazy sterilizing small portions of soil: I'm not really growing that much, but sterilizing soil for 10 or 15 11L pots is a bit of soil and work really(for my lazy ass at least ;) )

thanks for the replys everyone.
 
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