Sterilizing soil/compost with a microwave?

Pullin' weeds

Well-Known Member
Hello all,
Long time stealth grower - short time lurker - first time poster :mrgreen:

I've wanted to use the compost from my backyard bin for sometime, but didn't really relish the idea of having unknown wee-beasties running around my grow cabinet.

So I had the idea of heat sterilzing it in the microwave - about 5 minutes for 2-3 quarts of soil. Temps reach boiling -212, and I don't see any movement of micro worms or bugs.

After cooling I reinnoculate the soil with mycorrhizae additive to bring back the good bacteria - I hope.

Anyone have thoughts on this?
 

potpimp

Sector 5 Moderator
Sounds like a great idea. I don't know that you'd need to nuke it that long. You could do a sacrificial bug and see how long it takes to pop, LOL. Sorry... it's for science.
 

Pullin' weeds

Well-Known Member
I didn't think I'd have to nuke it so long either - but after 3 minutes I was amazed when I looked at the surface - little worms and bugs crawling everywhere. I'm guessing everyone made a break for the surface when the soil started heating up.

After 5 min, I didn't see anything moving anymore.
 

mmmfive

Active Member
I didn't think I'd have to nuke it so long either - but after 3 minutes I was amazed when I looked at the surface - little worms and bugs crawling everywhere. I'm guessing everyone made a break for the surface when the soil started heating up.

After 5 min, I didn't see anything moving anymore.

that's funny because i think they are safer in the soil. because when they rise to the surface, they get microwaved! haha so they had 2 options. stay in the soil and get steamed to death. or do whats natural and go up to the surface, to think you made it, but you start to feel stupid and next thing you know you're dead already. =/
 

scias

Well-Known Member
microwaves work from the inside center outwards. they prolonged their life by a few moments, poor critters :(
 

m3atwad

Active Member
lmfao
thats fucked up watching bugs getting nuked.
and yeah microwaves go from the center out.
so basically they just got fucked up
either way they were dead.
poor buggies.
 

WickedBuzz

Active Member
Hey man, I don't mean to be an organics nazi here, but if you nuke your soil, it changes the chemical composition, and technically its not organic soil any more.
I use sludge from my compost for my babies, worms n all !! They don't crawl around, they are happy in the pot. Coz thats where all the goodies are :) and there's plenty for everyone - they shit it out and go looking for more.
my babies love it. I think you have to think about it ecologically if you really want the most natural buds. People say you get less yield this way, but they are flourishing. So I guess we'll see...
I also spray the roots with one part worm juice, once part water.
They love it. Organic all the way:mrgreen:
 

speedhabit

Well-Known Member
I know this is all good, gettin the parasites out and all that but....your a monster



PS. First post!
 

o2hustla

New Member
hi all, i always nuke my compost because ive lost quite a few seedlings to little bugs. they seem to eat everything and just leave the seed shell. about 5 min on full power usually does the trick lol. i dont add any nutes to the nuked soil and all my plant have done ok so far. im all for nuking lol
 

SenorSanteria

Well-Known Member
hi all, i always nuke my compost because ive lost quite a few seedlings to little bugs. they seem to eat everything and just leave the seed shell. about 5 min on full power usually does the trick lol. i dont add any nutes to the nuked soil and all my plant have done ok so far. im all for nuking lol
I also nuked my soil. But first I froze it. Thats right- I put it in the freezer until it turned into a solid block... then it went right into the microwave. I broke it up into smaller peices and nuked it until it began to steam- about 2 minutes or so. If there was anything living in there... its not alive anymore. :mrgreen:
 

miggzeh

Well-Known Member
Is it a good idea to put a couple of worms in your pots or will they multiply too much and cause problems?
 

bongspit

New Member
I have an active compost system I use for my veggies and I also used it for my good plants...I bag it in air-tight bags and that seems to do the trick...:blsmoke:
 

Nullis

Moderator
Hello all,
Long time stealth grower - short time lurker - first time poster :mrgreen:

I've wanted to use the compost from my backyard bin for sometime, but didn't really relish the idea of having unknown wee-beasties running around my grow cabinet.

So I had the idea of heat sterilzing it in the microwave - about 5 minutes for 2-3 quarts of soil. Temps reach boiling -212, and I don't see any movement of micro worms or bugs.

After cooling I reinnoculate the soil with mycorrhizae additive to bring back the good bacteria - I hope.

Anyone have thoughts on this?
Kind of sounds like a terrible idea, to me. Mycorrhizae isn't bacteria but fungi, and there should actually be a plethora of organisms in your compost: bacteria\archae, fungi, protozoa and nematodes - even micro-arthropods are mostly beneficial.

If you have a healthy pile the good should well out number\out-compete the bad. If you have a hot pile (thermophilic) most of the insects and their eggs should be destroyed when the temperature peaks. Also once the compost is finished and if you separate it from the greater pile remaining bugs will wonder off. These things still don't guarantee that there wont be any pests in the finished compost, you'd need an analyses from a soil lab to confirm that, but as others have noted nuking or sterilizing changes the composition of the compost and worst of all it will kill virtually any living organisms within it- not a good thing in organics.

Compost is such a great inoculant because it naturally has a broad spectrum of lots of different organisms, or what we call bio-diversity. Once you nuke it you'll have quite a time attempting to restore all of the beneficial life that was present... I'd have to say it is damn near impossible considering that tens of thousands of species of bacteria, thousands of species of fungi (mainly chemoheterotrophic) and at least a hundred more species of protozoa, nematodes and other organisms were potentially alive in that compost.
 

Nullis

Moderator
Oh no, two and half whole paragraphs!

You don't even need a microwave to know what effect four minutes on HIGH or what extreme heat in general is going to do to the living things in the compost. You'll never restore the bio-diversity with mycorrhizae or any other horti-inoculant product because there should have been much more life in that compost than you'll find in any bottle.
 
Top