Boiling the peat?

BunsenH

Plant
I've started rinsing my peat moss/perlite, in preparation for repotting. I've read that one should rinse with tap water several times, leaving the slurry sitting for a few hours each time, until it runs clear, then a couple of rinses with distilled water. (Our cat seems to be very keen on drinking the peaty liquid. I've heard that some alcoholic drinks have a "peaty" note, and have wondered how people identify that flavour.) The process would probably be faster if I brought the stuff up to a boiling temperature, but I've read warnings that that would kill beneficial microorganisms. That sounds reasonable. But... what about doing it, then "inoculating" the result with a small amount of untreated peat moss?

The idea may be partially inspired by Robert Heinlein's juvenile novel Farmer in the Sky, which describes the process of turning rock dust into "living" soil suitable for farming.
 
It may depend on one's source. I've been using a big bag of the stuff from my local Loblaws-chain store. I don't completely trust that my "horticultural-grade perlite" is free of soluble substances, either. "Better safe than sorry" seemed prudent.
 
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I guess it's never wrong to take precautions. Still you don't want to make a fun hobby onerous.
Still for difficult cacti seeds, I microwave the medium, sterilize the rain water and mix it with No-Damp, plus occasionally dusting with powdered sulphur. Sometimes precautions are necessary or worth it.
 
Boiling peat will cause the media to degrade faster. I have found that just rinsing a couple time is enough to wash away most mold spores and algae. I have never had a problem with Dionaea seedlings damping off with or without rinsing the peat.
 
I rinse with distilled water and microwave all material (peat, perlite, sand, LFS, etc). Occasionally, instead of microwaving I'll drench the material with very hot distilled water. Used but relatively new mixes get a quick microwave before re-use. Simple precautions.
 
How hot do you get your material by microwaving it? If it's not getting hot, I'd be astonished if the microwaves affected microorganisms directly.
 
When I sterilize medium for cactus seeds, I put some water in with it and microwave till it boils and repeat a few times. There may be a few hardy spores but way more will come from the air afterwards anyway.
 
@BunsenH The medium is damp when microwaved. Typically, it's heated in a Pyrex bowl using mid-power until the medium is too hot to touch. Duration depends on the material and quantity. It's certainly not sterilized like instruments in an autoclave but probably is adequate to eliminate most pathogens or wayward seeds.
 
@BunsenH The material is damp after rinsing. I microwave it at medium power until it is too hot to touch. While it's not as precise as sterilizing instruments in an autoclave, it eliminates most pathogens and kills wayward seeds.
 
I have a lot of scotches on my shelves with peaty notes, I fully understand your cat.

I also do nothing to my peat mixes, haven't done so in 45 years or more and at least with the peat we get over here, I have never had a problem. The peat is generally PH4 ish so it has its own inhibitor.

Cheers
Steve
 
You can completely sterilize in a microwave. I have instructions for tissue culture. Of course in tissue culture the sterile state is (hopefully) maintained. Otherwise the moment the heat is off, spores colonize the medium. It is theoretically possible that the microbial state could be more pathogenic after sterilization, as benign organisms would be killed and household mould might take over quickly. I'm not sure if that's practically important. As @steve booth mentioned, you generally don't have to heat, rinse etc. most plant media.
It's the same as personal hygiene or keeping your rooms clean. Certain levels of cleanliness are generally considered as good but there is a law of diminishing returns. Everyone's standards are different.
 
I don't do anything fancy to my peat, I just slam it with tap water until the ppm gets down to my tap levels then I do four or so heavy flushes with distilled until ppm is under 50 then I do a slam of H2O2.
 
If you measure the TDS of wet peat, it will mainly reflect organic acids which are normal for peat bogs. Not harmful to plants. The H2O2 will not do much to microbes as it will be quickly neutralized by the peat itself.
 
If you measure the TDS of wet peat, it will mainly reflect organic acids which are normal for peat bogs. Not harmful to plants. The H2O2 will not do much to microbes as it will be quickly neutralized by the peat itself.
Yeah but the I can still piggyback off the TDS as a zeroing reference point so I get some kind of standard in my pots.

I know the H2O2 won't stick around but it will still immediately kill any bugs, fungal, moss and mould spores. I've noticed a reduction in nasties between doing it versus just slapping the peat in and going to the races
 
I’ve definitely decocted peat moss that I got from a small hardware store. I smelled mildewy and mouldy when I got home.

I hear y’all on microwaving. I don’t have one so thats that.

I have actually been using coconut coir and sand as my planting medium and my plants are very happy. The coir breaks down even slower than peat. I have learned the lessons of not rinsing the products I get from the store. So I listen to the folx who have been doing carni’s for decades on that.

I feel very skeptical on "ethical harvesting" of peat. Everyones ethics are different. I appreciate that the coir is a byproduct of another industry, instead of digging up the wetlands.

Thats my two cents… I hope this helps.
 
I've got some sisal fibre, from the rope that used to wrap our cat tree, which I've boiled several times until it's odourless. I've been thinking of cutting it into short lengths to see if that might work, mixed with perlite, for transplanting a couple of my seedlings to. Just as an experiment, since I've got the stuff on hand. It seemed to do okay last year just to support the plants during their dormancy.
 
I’ve definitely decocted peat moss that I got from a small hardware store. I smelled mildewy and mouldy when I got home.

I hear y’all on microwaving. I don’t have one so thats that.

I have actually been using coconut coir and sand as my planting medium and my plants are very happy. The coir breaks down even slower than peat. I have learned the lessons of not rinsing the products I get from the store. So I listen to the folx who have been doing carni’s for decades on that.

I feel very skeptical on "ethical harvesting" of peat. Everyones ethics are different. I appreciate that the coir is a byproduct of another industry, instead of digging up the wetlands.

Thats my two cents… I hope this helps.
How often/what steps do you take to rinse the coir?
 
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