what makes your mix great

[Gareth]

hi joel,

I didnt say it was sterile, nor did i say organic ferts dont work well in inorganic mixes.

Anyone who really knows thier biological medias, like i am about to tell you, will be able to tell you that the pores in diatomie are so small, that they hold water, but the bacteria soon clogs the pores and dies, making it an inhospitible environment for bacteria to live.

It a case of usable surface area verses actual meausre surface are (which in a good amount of cases is useless).

My point i am trying to ake, is that with more organic material in the mix, it creates a more hospitable and desireable place for bacteria to live,, and therefore the amount of bacteria per unit mass of potting media is much higher, therefore making the breaking and subsequent availablility of organically available nutrient from biological breakdown higher than in an inorganic mix.

note that all this time i have pointed out both the advantages and disadvantages of BOTH types of medias organic and inorganic. and not once have i said inorganic is bad or should not be used.

I dont think i ever said the substrate getting decomposed was relevant or irrelevant, simply that organic particle in the mix at higher concentration allows the breakdown or organic substances into plant available nutrient.

[Joel]

Hi Gareth,

I was not accusing you of such. I was trying to disprove a myth frequently circulated on this forum. My comment was more of a response to pups post than yours. Sorry if I came across offensive.

Joel

[Gareth]

no worries man.

Just remember, when it come to surface area and how it relates to bacteria, weather it is in soil or water, if you cant see how the water would flow through it, and stop the build up of detritus, then chance are the surface area being claimed, is not usuable.

All well and good for something to have a huge amount of surface area, but when it become bloked with muck and dead bacteria, only the surface on the outside is actually usable by the bacteria, becuase the bacteria need to be able to respire and have nutrient carried to them by water to survive. if the pores they are in clog up, then they die.

Look at the surface area for matrix, and then look at the surface area for marine pure ( the vlaues i mean). then put them side by side and see which one you think would allow water to flow more freely through, and prevent the build up of detritus.

weather it abosrbs water or not is irrelevant when it ocme to bacteria, if the environment where the water is in anoxic and clogged with crud and dead bacteria, they cant live in there, and therefore all that "surface area" is useless.

[The Specimen]

Potting medium.. ok here we go as i am sure our trees sure can benefit right.. this is the idea??

Well atm, im all over the place.

I recently bought scoria (seems rather chunky ar 3-8mm after sieve) and am trialing that with various other midiums "at hand"

I have 2-7 diatomite though my zeolite is quite small I also have sifted bark and gonna get pine nuggets soon.

For me, scoria is readily available and cost effective and would love to use this as "the main" with additives though for the reasons
and concerns already mentioned, i have also started to add a little organics to the mix for fear that my trees will suffer at the current concoction of just scoria n pine bark alone with pellet fertz thrown in.

Are my newly potteds' at risk from the elements or there the lack of?

Current: 55% scoria, 35% pine bark & 10% fert made up of 50/50 chook poo n D/Lifter

Concern: drying out too quick n little to no nutrition


COMMENTS/THOUGHTS/TIPS/ADVICE PALEASE

[Luke308]

Potting medium.. ok here we go as i am sure our trees sure can benefit right.. this is the idea??

Well atm, im all over the place.

I recently bought scoria (seems rather chunky ar 3-8mm after sieve) and am trialing that with various other midiums "at hand"

I have 2-7 diatomite though my zeolite is quite small I also have sifted bark and gonna get pine nuggets soon.

For me, scoria is readily available and cost effective and would love to use this as "the main" with additives though for the reasons
and concerns already mentioned, i have also started to add a little organics to the mix for fear that my trees will suffer at the current concoction of just scoria n pine bark alone with pellet fertz thrown in.

Are my newly potteds' at risk from the elements or there the lack of?

Current: 55% scoria, 35% pine bark & 10% fert made up of 50/50 chook poo n D/Lifter

Concern: drying out too quick n little to no nutrition


COMMENTS/THOUGHTS/TIPS/ADVICE PALEASE

Hey mate,

I found putting DL or any pellet type fert into the mix is dangerous and I lost a nice liquidambar because of this. I think it comes down to root pruning and fertilising too soon. As I'm sure you have read/heard we shouldn't fertilise of 6 weeks after root pruning as it can burn the roots.

The only trees that I think you could do this with (and I haven't tried this but have seen success from the thread on it) is figs as found in the "how to develop dynamic figs quickly" thread. I think someone already mentioned in this thread that your better off using DL and pellet ferts in stocking/tea bags on top of substrate as this reduces the risk of going hard crusty.

[Joel]

no worries man.

Just remember, when it come to surface area and how it relates to bacteria, weather it is in soil or water, if you cant see how the water would flow through it, and stop the build up of detritus, then chance are the surface area being claimed, is not usuable.

All well and good for something to have a huge amount of surface area, but when it become bloked with muck and dead bacteria, only the surface on the outside is actually usable by the bacteria, becuase the bacteria need to be able to respire and have nutrient carried to them by water to survive. if the pores they are in clog up, then they die.

Look at the surface area for matrix, and then look at the surface area for marine pure ( the vlaues i mean). then put them side by side and see which one you think would allow water to flow more freely through, and prevent the build up of detritus.

weather it abosrbs water or not is irrelevant when it ocme to bacteria, if the environment where the water is in anoxic and clogged with crud and dead bacteria, they cant live in there, and therefore all that "surface area" is useless.

Makes sense Gareth.

I have not done comparison rates of chemical breakdown. Not even sure how you would go about that.

I personally use organic ferts in my inorganic media with great results. All I meant to say was that there is sufficient biological activity to break down the fertilisers I use into products the plants can use.

Interestingly, I have started adding small quantities (roughly 5 percent of my mix) of composted pine bark in an attempt to increase biological activity. I can't say I have noticed a difference but recently I had a small Mycena sp. mushrooms pop up in a few of my containers, both completely inorganic and the new mix. I repotted one of the inorganic ones to check it's roots for fear that this mushroom, being saprophytic, was an indicator of dieback in the roots. Nope, no damage. I can only assume it was getting it's nutrients solely from the various organic fertilisers I use.

Joel

[Gareth]

yep, there is no doubt organic ferts work in inorganic mixes, and there is some bacteria in the mix in an inorganic potting media.

However, one of the advantages of adding larger amounts of organic material is that there is a much larger volume of environment conducive to supporting microbiological activity, so it thrives, rather than just survives.

this could very well mean, and i am just hypothesizing here, that any organic fertilizer added to the mix that gets soaked up by the organic component of the mix, would be utilized to a higher percentage than in an inorganic mix where it may possibly be flowing straight through the mix.

Also, because organic soils and particles are commonly much smaller than inorganic grains, it absorbs much more water/liquid fertilizer, being that poer unit of liquid fertilizer you put in, theoretically you could be utilizing and keeping in the mix, much more of the fert your adding.

More fert kept in the mix means more fert available to the plant, more bacteria in the mix, coupled with more orgnic particles and nutrients in the mix to break down into plant available nutrient, means a higher nutrient uptake to the plant, equaling more growth and a healthier plant, which, could also possibly mean using less fertilizer, Maybe.

[The Specimen]

Hi Luke,

Thanks for the info as I never knew about the 6 week rule.. could save me some trees there so

When repotting, just dont fertz with pellets into the mix right?



Ok think my feeding is on a good path.. now just for for the SCORIA & PINE BARK.. anyone with any info PALEAESE

[craigw60]

My experience with potting mix are based purely on observation with no scientific background. I have been using the same mix for many years both when living in the western suburbs of Melbourne and here in the dandenong ranges, two very different climates. Its roughly 50/50 diatomite and pine bark both components are put through a 1mm sieve to remove any fines. My only goal is to achieve good drainage and I find if all the components of the mix are roughly the same size then the drainage is excellent. I would never consider mixing any thing other than osmocote in with the mix the addition of D/L is really going to clog up the mix and I can't see a big advantage when its so easy to feed from the surface.
Craigw

[Pup]

Hi Gareth,

I was not accusing you of such. I was trying to disprove a myth frequently circulated on this forum. My comment was more of a response to pups post than yours. Sorry if I came across offensive.

Joel

I am not a scientist, never claimed to be. I just GROW GOOD Bonsai in my mix.

So it must be good. No science just good trees. I had never tested my PH until a month ago it was perfect to my surprise. No science just good trees.

PUP

[treeman]

Hi all, Its obvious that good quality plants can be grown in a huge range of mixes. Inoranic and organic or combinations. I think one of the most important qualities in a mix is water management. That is, If your in a wet climate, you sould select a mix which is capable of shedding more water than if you lived in a dry climate. For instance comparing Nth. America or most of Europe where they get regular summer rain with the Mediteranian or Southern Aust. or Southern California, it stands to reason that those in the summer-dry areas should use a mix which retains more water. If I used a wholly inorganic mix here, I would need to water 3 times a day during the summer. (something I'd rather not do) therefore I incorperate at least 60% organic ( composted pinebark ) in my mixes and lately I have been reducing particle size to about sugar-grained size for small pots. A lot of folks seem to be overly obsessed with trying to emulate Japanese-type particle size mixes, and while they can give great growth response, You really have to keep on top of them with the water!
I think for Australian conditions (dry), using at least 50% organic is the way to go. I've used diatomite as the mineral component but I've never really noticed any outstanding advatage over course sand ( as long as the bark is screened properly).
As far as fertilizing is concerned, a slow release form (cakes or osmo.) will ensure plenty of nutrients arriving at your tree's roots whether its organic or mineral. Including 10% zeolte to your inorganic mix will ensure plenty of CEC.
Conversion of Urea to ammonium and ammonium to nitrate will take place in any mix pretty quickly. If the fert. is there so will the bacteria be. The thing to watch is bacterial activity will diminsh in winter in cold areas. That why your trees can look a bit yellow in late winter. A few hits of inorganic liquid fertilizer during this time should help.

[old_skool]

Newby question guys, should mixes be measured by volume or weight?

Cheers,
Adam

[Gareth]

in my opinion, because each componenet will way differently, and the objective is to get the % distribution in the pot, the only constant factor is volume.

For instance, 1L of zeolite weighs more than 1L of diatomite.

Measurieng by volume will ensure that the % of each compoenent you use is accurate.

I like to calculate the the volume of the container im using to re-pot, then mix up this amount, or a little more of the potting media to ensure i have enough, this way, if you have say 20 liters, and as an example your mixture is 40% diatomite, 20% zeolite, 30% organic and 10% coco peat, then you simply calculate what each volume in liters is of each compoenent and use a graduate jug or 1 or 2 liters or similar to meaure each compoenent out.

so liters in this mix for 20 liters would be

8 liters diatomite, 4 liters zeolite, 6 liters organic, 2 liters coco peat = 20 liters.

if you were to meaure by weight, each compoenent needs to weigh exactly the same amount in order for then to be calculated equaly as a percentage in the mix. and as they do not, the only constant is volume , most commonly measured in liters, at least that what i use because its easy.

[kcpoole]

Disadvantages of inorganic mixes

- needs a lot of watering to keep it moist (no soil to hold excess water)
- have to fertilize a lot, and often
- dry out quicker than a mix with organic in it
- very little microbiological breakdown of nutrient

Nice summary, but I disagree with the above statements.
-For me I have done a few moisture tests with Diatomite v Ray Nesci mix and both take similar times to dry out. The plant comparison tests bear this out too. Privet in different mixes will wilt from lack of water slower in diatomite.

-Have to fertilise as much as anything else. Some users of Organic mixes fertilise daily anyway so really does not matter what the growing medium is. I have never changed fert Regimen when I started using in-organics, and cannot see any difference in Health or goring rates because of it.
the way I think is that after a few months, Any nutrients will be leached out of ANY mix because we water so often. Virtually all Nutrients for the tree must come from what we add to the mix as Fertilizer.
How much is retained in the medium depends on the cation ratio of the components. As Damian mentions here, adding zeolite to pine bark will increase its cation ratio viewtopic.php?f=12&t=8602&p=94474&hilit ... tio#p94481 .

-Dry out Quicker? see above, but I disagree

- very little microbiological breakdown of nutrient? Huh, I reckon that has to be a benefit of in-organics, not a disadvantage

Ken

well i guess ill just shut up then...............

No need to mate I was not being aggro at all, but wanting to counter the fallacy that the original quote of yours made and lead people to continue to perperate the myths.
- needs a lot of watering to keep it moist (no soil to hold excess water)
- have to fertilize a lot, and often
- dry out quicker than a mix with organic in it

On my benches, those 3 statements do not apply.

Like Pup, I have no scientific / Hort background, but just know what works and what does not. I am prpeared to experiment to get alternative knowledge as it applies to me.

Ken

[Matthew]

my mix is basically the same as craigW maybe a little more diatomite for pines, junipers otherwise identical. Used it for 3 years here now and even in winter when things are constantly wet is performs great.