To cook or not to cook?

[papa canna]

A friend of mine was telling me about a new soil mix hes been using. a very simple concoction of 3 different pre mixed bags of soil from the local shop. My friend has much more experience than I do, so I should really take his word at most things. But I asked him If I should cook up this mix while the weather is warm seeing as I wont need the medium for about another month.

My friend says not to. Even the guy at the hydro shop (I know, dont say it) said he wouldnt recommend it either. They both said it would be fruitless labor that the soil is already as ready as its going to get. The only "dry nutrients" I would be manually adding in is just a bit of EWC. Would you cook prebagged soil? Does it make sense?

 

[SouthCross]

The bags of soil might be a year old....Might be 6 months...

Premixed soil has a shelf life. There's a point of diminished returns. From what I've read, Its a year. After that the nutrients in soil decline in strength and amount. The only way to stop it is to store the soil bone dry. Moisture activates it.

Cooking a premixed bag of soil is wasting time and money. You want it fresh as in around a month old. The clock keeps ticking if it contains any water.(which it does)

 

[calliandra]

The only time you're going to "cook" soil is after adding hot amendments that you want processed a bit before you add the plant.

Otherwise, there is still an argument for setting up a pot and letting it sit for a while: if you have a good fungal potential that will thus get the opportunity to reestablish (adding some compost tea or extract to promote that).

Otherwise, what SouthCross said, plus factor in possible storage glitches (bags left in rain/scorching sun/frozen over suddenly=dead microherd)

 

[Rasta Roy]

The bags of soil might be a year old....Might be 6 months...

Premixed soil has a shelf life. There's a point of diminished returns. From what I've read, Its a year. After that the nutrients in soil decline in strength and amount. The only way to stop it is to store the soil bone dry. Moisture activates it.

Cooking a premixed bag of soil is wasting time and money. You want it fresh as in around a month old. The clock keeps ticking if it contains any water.(which it does)

The microherd in bagged soil will decrease and in all reality die pretty quickly, but the nutrients in soil aren't going to go anywhere if nothing is growing in it, or no water is running through it and causing erosion.

Now if the company that made the soil made poor component choices, or didn't finish composting (cooking) the soil before they bagged it...than some nitrogen in the soil would turn into a gas and leave the soil over time.

 

[Rasta Roy]

No need to cook prebagged soils!

Cooking is just composting, and you only need to do it if you're mixing a heavy amount of readier releasing Nitrogen fertilizers (blood meal, chicken shit, bat Guano).

 

[SouthCross]

The microherd in bagged soil will decrease and in all reality die pretty quickly, but the nutrients in soil aren't going to go anywhere if nothing is growing in it, or no water is running through it and causing erosion.

Now if the company that made the soil made poor component choices, or didn't finish composting (cooking) the soil before they bagged it...than some nitrogen in the soil would turn into a gas and leave the soil over time.

The way I understand it. The soil being moist, it's the microherd itself that's also eating the nutrients. Over application of compost tea can lead to the microherd consuming too much nitrogen. They start to compete with the plant.

So, After a year, the nutrients have been depleted.... eaten by the soil critters themselves. With no insects dying, birds/animals crapping, and dead foliage adding back to it. It's a limited supply of food.

 

[Rasta Roy]

The way I understand it. The soil being moist, it's the microherd itself that's also eating the nutrients. Over application of compost tea can lead to the microherd consuming too much nitrogen. They start to compete with the plant.

So, After a year, the nutrients have been depleted.... eaten by the soil critters themselves. With no insects dying, birds/animals crapping, and dead foliage adding back to it. It's a limited supply of food.

The microherd is taking the organic matter, and minerals and the nutrients within them and putting them in a more plant uptakeable form. They consume the matter yes, but to shit it out so your plants can use it.

 

[xmobotx]

you can mix in a fashion that it's no problem to plant in to that fresh mix. and, it can be a "strong" enough mix to carry plants for a while as water only. it's beneficial to have a living, aged component as good compost/EWC or some recycled mix.

essentially, as a goal, nutrient cycling {composting w/ amendments going through the compost cycle} should be accomplished & w/ a fresher, beginning mix, less nutrient cycling having been accomplished, more time for this process to get started must be allowed. tangentially, the higher quality of the aged, living components {humus sources} the less cook time may be necessary & a "stronger" {higher EC} may require less time when that humus quality is high.

i make a weak mix then, top~dress later when i need fresh soil to transplant in to. not like a seedling mix of "peat, drainage, humus, Ca amendment only." a mix w/ some neem/crab/kelp {&/or fish bone, fish meal, alfalfa, manures} ~maybe 1/4 as much

 

[greasemonkeymann]

A friend of mine was telling me about a new soil mix hes been using. a very simple concoction of 3 different pre mixed bags of soil from the local shop. My friend has much more experience than I do, so I should really take his word at most things. But I asked him If I should cook up this mix while the weather is warm seeing as I wont need the medium for about another month.

My friend says not to. Even the guy at the hydro shop (I know, dont say it) said he wouldnt recommend it either. They both said it would be fruitless labor that the soil is already as ready as its going to get. The only "dry nutrients" I would be manually adding in is just a bit of EWC. Would you cook prebagged soil? Does it make sense?

depends on the intent, if the mix was intended more for a mix for flowering plants had either bone meal, granite dust, greensand, langbeinite, etc. then it could be useful for allowing that to be cycled
also i would totally have no problem aging soil simply to keep the microbial diversity going.
the biggest loss will always be nitrogen, but its also the easiest nutrient to add also.

 

[natureboygrower]

a little off topic @greasemonkeyman but i had a bunch of that soil leftover you helped with.its outside under a tarp.would this mix be suitable for indoors and how would you store that for future use(a couple months from now) bug/pests concerns about bringing them indoors...

 

[greasemonkeymann]

A friend of mine was telling me about a new soil mix hes been using. a very simple concoction of 3 different pre mixed bags of soil from the local shop. My friend has much more experience than I do, so I should really take his word at most things. But I asked him If I should cook up this mix while the weather is warm seeing as I wont need the medium for about another month.

My friend says not to. Even the guy at the hydro shop (I know, dont say it) said he wouldnt recommend it either. They both said it would be fruitless labor that the soil is already as ready as its going to get. The only "dry nutrients" I would be manually adding in is just a bit of EWC. Would you cook prebagged soil? Does it make sense?

stupid double post...
edit...

 

[greasemonkeymann]

The way I understand it. The soil being moist, it's the microherd itself that's also eating the nutrients. Over application of compost tea can lead to the microherd consuming too much nitrogen. They start to compete with the plant.

So, After a year, the nutrients have been depleted.... eaten by the soil critters themselves. With no insects dying, birds/animals crapping, and dead foliage adding back to it. It's a limited supply of food.

ya got it sorta a lil off, the microbes consume the carbon, they don't actually consume all the nutrients, they convert it.
remember matter can't disappear without being used, sorta the same concept as cow manure or whatnot, all the plant material is still IN the cowshit, it's just a different form of it.
same concept as co2 from composting, ammonia gasoff, etc
but given the correct ratio of carbon to nitrogen and 99% of the nutrients will still be there.
otherwise think about it, nearly all fields would be devoid of all nutrients from all the microbes present eating the nutrients, not to mention it'd be a rather antagonistic relationship between the two

 

[SouthCross]

ya got it sorta a lil off, the microbes consume the carbon, they don't actually consume all the nutrients, they convert it.
remember matter can't disappear without being used, sorta the same concept as cow manure or whatnot, all the plant material is still IN the cowshit, it's just a different form of it.
same concept as co2 from composting, ammonia gasoff, etc
but given the correct ratio of carbon to nitrogen and 99% of the nutrients will still be there.
otherwise think about it, nearly all fields would be devoid of all nutrients from all the microbes present eating the nutrients, not to mention it'd be a rather antagonistic relationship between the two

Shelf Life. Point of diminished returns? Nobody is advertising their bag of dirt as being aged. Why?

 

[greasemonkeymann]

A friend of mine was telling me about a new soil mix hes been using. a very simple concoction of 3 different pre mixed bags of soil from the local shop. My friend has much more experience than I do, so I should really take his word at most things. But I asked him If I should cook up this mix while the weather is warm seeing as I wont need the medium for about another month.

My friend says not to. Even the guy at the hydro shop (I know, dont say it) said he wouldnt recommend it either. They both said it would be fruitless labor that the soil is already as ready as its going to get. The only "dry nutrients" I would be manually adding in is just a bit of EWC. Would you cook prebagged soil? Does it make sense?

the simple preface of the highlighted statement from you is a perfectly valid reason to age the soil.
the added ewc is a type of inoculation, and the majority of those bacterial microbes will likely not be found in the prebagged soil, so you'll have a much better foundation of a living soil after that.
yea, there are easier ways to do that, but i'd have no problem at all with a soil that's been aged.
I do that all the time, all my soil is well over 5 yrs old, some is 10 yrs old even.
as we speak I have probably a good 350 gallons of soil chillin in a gigantic smartpot, and it's a quasi wormbin/compost type thing.

 

[greasemonkeymann]

Shelf Life. Point of diminished returns? Nobody is advertising their bag of dirt as being aged. Why?

ok, well, where does it go then?
I apologize if I seem to be a lil aggressive but I have a fairly comprehensive understanding on how the scientific compost process works, and unless there is a new way of nutrients being leached out of the soil I don't see how any of that is being lost.
past an improper ratio of nitrogen to carbon how does it disappear?
and to be honest?
the advertising I've seen from anyone making bagged soil is not exactly scientific, so basing an argument on that is less than convincing.
again, think about it.
what would happen if the microbes and the plants needed to consume the exact same things?
seems to be a, umm, flawed system if that were to be true...
wouldn't you agree my man?
they have a symbiotic relationship, from the root exudates to the mychorrizhae to the humus being made to the nutrients being chelated biologically, it's all a very very fine tuned system evolved to be about as perfect as you could expect.
nutrients often increase as composting is finished, with potassium being the most that is "created"
in actuality it's merely being made available, but it's still increased as composting happens

 

[greasemonkeymann]

here is some related information
copy and pasted
website is at this address

http://www.fftc.agnet.org/library.php?func=view&id=20110913155219

3.4.1 Nutrient Balance_carbon/Nitrogen Ratio
Nutrient balance is very much dependent on the type of feed materials being processed. Carbon provides the preliminary energy source and nitrogen quantity determines the microbial population growth. Hence, maintaining the correct C:N ratio is important to obtain good quality compost. Bacteria, actinomycetes, and fungi require carbon and nitrogen for growth. These microbes use 30 parts of carbon to 1 part of nitrogen. Composting is usually successful when the mixture of organic materials consists of 20-40 parts of carbon to 1 part of nitrogen. However, as the ratio exceeds 30, the rate of composting decreases. Further, as the ratio decreases below 25, excess nitrogen is converted to ammonia. This is released into the atmosphere and results in undesirable odor (Pace et al. 1995).

During bioconversion of the materials, concentration of carbon will be reduced while that of nitrogen will be increased, resulting in the reduction of C:N ratio at the end of the composting process. The reduction can be attributed to the loss in total dry mass due to losses of C as CO2 (Hamoda et al. 199. Ammonium-N (NH4-N) and nitrate-N (NO3-N) will also undergo some changes. NH3 levels were increasing in the initial stages but declining towards the end (Liao et al. 1995). In several instances, NO3 concentrations were less during the initial phases but gradually increased towards the end (Neto et al. 1987) and, in some instances, remained unchanged (Palmisano et al. 1993). Maintaining NH3 concentration is important to avoid excess nitrogen losses and production of bad odor. Maintaining C:N ratio after composting is also important to determine the value of finished compost as soil amendment for crops. The final C:N ratio of 15 to 20 will be expected and the value of more than 20 might have a negative impact and will damage the crop and seed germination. The value of 10 has been suggested as ideal.

3.4.2 Phosphorus
Levels of P along with N and K will be important to determine the quality of compost, as P is also one of the essential nutrients for plant growth. A C ratio of 100 to 200 is desirable (Howe and Coker 1992). Phosphorus is not lost by volatilization or lixiviation during the composting process, but P concentration might increase as composting proceeds (Warman and Termeer 1996).

3.4.3 Sulfur
Presence of S in sufficient quantities can lead to the production of volatile, odorous compounds (Day et al. 199. The major sources of S are two amino acids, namely, cysteine and methionine. Under well-aerated conditions, the sulfides are oxidized to sulfates, but under anaerobic conditions, they are converted to volatile organic sulfides or to H2S, leading to a bad odor. Some compounds like carbon disulfide, carbonyl sulfide, methyl mercaptum, diethyl sulfide, dimethyl sulfide, and dimethyl disulfide might also lead to bad odors

 

[SouthCross]

Respect.

 

[SouthCross]

You just fed the information stream and I learned something new myself.

 

[calliandra]

http://www.fftc.agnet.org/library.php?func=view&id=20110913155219

Ah this is definitely the most accurate and comprehensive write-up on the composting process I have seen to date - thanks for sharing!

the simple preface of the highlighted statement from you is a perfectly valid reason to age the soil.
the added ewc is a type of inoculation, and the majority of those bacterial microbes will likely not be found in the prebagged soil, so you'll have a much better foundation of a living soil after that.

Absolutely! - seems I missed that too on my first reading of the question.
Also, that includes not just bacteria, but the whole team of decomposers and predators needed to get nutirent cycling going.

A few things I feel need straightening out from the posts in this thread for the sake of conceptual accuracy:

Chemistry follows the biology.
The chemical composition (which, granted, is what we can assess rather reliably at the present moment) actually is just a symptom of the biological process (which, granted, is extremely diversified and which we only have a vague notion of at this point... or ever? considering the estimated number of species is rocketing upwards, not quite up-to-date estimates lying at 75K for bacteria and 25K for fungi, nevermind individual adaptation to specific environments, where microbes actively can change their DNA..!).
The actual initiating force is always going to be microbial activity and interaction. So while we do depend on the chemical findings, we need to remember that is not the actual causal force. We're just following shadows of the real thing

Also, when our compost has this and that in chemical terms (usually an analysis of total nutrients), those nutes are actually tied up in the tiny microbe bodies and only get released when they get eaten by higher-trophic microbes with lower nutrient needs (=nutrient cycling). That's the reason compost doesn't leach nutes the way inorganic ferts just percolate straight through the soil into our rivers.
Take for example nitrogen, whose cycle has been studied. Bacteria have a very narrow C:N ratio of like 10. They get eaten by, say, an amoeba with C:N needs of like 30, so the extra nitrogen is released as poop into the rhizosphere, where it will be taken up by the plant. And the plant makes sure only those nutes it needs are in this soluble form at any time - by releasing exudates that will promote the growth of those microbes that can mine the nutrients required.
So when you go to analyse the soluble (=directly plant-available) nutes in a compost, they will be very low level.
Most of the magic is in the microbes. And if the composting went well, they are going to be aerobic and more of the foods consumed will be stored in their bodies (as opposed to gassing off as happens with anaerobic microbial activity).
And the same principles of course apply to the microbes in a prebagged soil, in our pots, and gardens.

 

[greasemonkeymann]

a little off topic @greasemonkeyman but i had a bunch of that soil leftover you helped with.its outside under a tarp.would this mix be suitable for indoors and how would you store that for future use(a couple months from now) bug/pests concerns about bringing them indoors...

whats going on my man?
so what I do with my soil after it's used is let it chill in my gigantic smartpot and depending on how long it'll be till I use it, I may or may not put a cover crop on it.
one of my favorites is simply grass, they tend to attract and need the same sort of bacterial interaction that cannabis does, not to mention it keeps the soil more "alive"
now in regards to pest control? I literally don't do a thing about that, considering my grows are in a very unsealed shed outside, in a redwood forest, so pest control isn't a possibility for me, so I'm afraid I can't offer much advice there.
i'd speculate that a garage would work alright, but past that it's gonna be hard to control any bugs, but that being said typically you don't get bugs from the soil itself, not unless the previous grow had bugs, but normally the "bugs" present in a soil will be the total opposite types of the ones that eat your plants, almost all of those are 'transient" type pests, mites from the wind, grasshopper/leafhopper, etc. all those actively go and LOOK for plants to infest, rather the soil critters are just chillin there

You just fed the information stream and I learned something new myself.

literally the sole reason that I am here my friend, I have a myriad of odd compulsive neurotic "needs" goin on, luckily one of them is to help people
now if only the other like 7 neurotic issues would be so benign..
I am happy to help in any way my man