Inorganic - I'm Convinced

[Wayne R]

I've read much on the internet and in this forum about the benefits of inorganic potting mixes. Unfortunately, my circumstances are such that I don't have access to nurseries other than the Blue and Green shed plus Coles, Woolies etc; I can't get hold of Akadama or any of those other exotic media. So what's a newbie to do? Grab what you can and experiment, obviously. I managed to source Zeolite from a cat litter (didn't turn to mush when wet), zeo-clor (alternate for pool filter sand) from the Green shed, scoria from local soil supplier (but this stuff is huge; about 15mm), course grit from the Blue shed and some standard potting mixes.

I needed a test plant and fortunately there are masses of a small flower appearing in my mum's garden that are as tough as nails (these things could grow on the dark side of the moon given half a chance) and three of them volunteered. I made up three different pot mixes and planted things up around 10 Sep 14. Each plant received Miracle-Grow weekly and the same amount of water each day. I stopped the test today to see how the plants fared.

Scientifically pulling each plant by the scruff of the neck out of it's pot I was amazed at how well two of the subjects had grown. A quick shake-off of remaining media showed the root development. I'm stunned and now convinced that inorganic soil mix is not only the way to go, but can be done cheaply and with readily available components.

Here's the results:

Mix A (not a success)
1.5 parts Scoria (about 10-15mm)
1.5 parts Course Grit
1.0 part Zeolite (>= 5mm)
0.5 parts Orchid Potting Mix

DSC_6826.jpg

Mix B
2.0 parts Course Grit
0.5 parts Zeolite (>= 5mm)
0.5 parts Premium Potting Mix

DSC_6824.jpg

DSC_6829.jpg

Mix C
1.0 part Course Grit
1.0 part Zeo-Clor
0.5 parts Premium Potting Mix

DSC_6825.jpg

DSC_6828.jpg

I found watering this mix far easier than with standard potting soils and am blown away by the root development. It's inorganics for me from now on.

[kcpoole]

what a great result
The next test is to see how it perform for you over the next few months of summer.

Does the mix hold water for the trees as long as the control ? or does the trees suffer stress sooner or later than the control

Keep us posted

Ken

[Bougy Fan]

Did you do a control pot with a good quality potting mix ? I would have been interested to see those results too. I don't think you gave scoria a fair go using 10-15mm particle size. I use about 7mm size with sifted diatomite and have great results. Just watch the zeolite - I have stopped using it as for my needs it keeps the mix too wet.

[Sammy D]

Good result. Dont discount the scoria to quick though. I use 1 part scoria to 1 part vermiculite and 1 part potting mix. So far so good. Still testing but they sevived last summer. (Hottest summer on record) think we went 14 days straight over 38 in murray bridge with some over 45. vermiculite really helps with the moisture while also allowing the roots to breath. The ones I repotted in this mix had a lot of roots and they also grew well all summer. And growing well this summer. Doesnt hurt that i can get free vermiculite. Anyway well done. More than one way to skin a cat looks like your mix works well.

[Wayne R]

Did you do a control pot with a good quality potting mix ? I would have been interested to see those results too. I don't think you gave scoria a fair go using 10-15mm particle size. I use about 7mm size with sifted diatomite and have great results. Just watch the zeolite - I have stopped using it as for my needs it keeps the mix too wet.

No, I didn't do a control pot as that is not new for me. I really have no probs using prem potting mix and/or camellia potting mix (the plant will grow), but I really wanted to try the inorganic route for when I start putting things into small bonsai pots. I can't get scoria in a smaller size without driving further afield and in that regard I am limited to time after 6pm which doesn't sit well with the soil suppliers.

The main thing I got from this test was how well, and dense, the roots grew and how easy it was water... I'm one of those who tend to over-water (typical noob) and with the inorganic mix over-watering is hard to do.

I'd love to try diatomite but just don't have access

[kcpoole]

YUou can get Diatomite from Enfield Produce in Sydney. They will ship but have no idea on cost, and can you do so to WA?

Ken

[Wayne R]

YUou can get Diatomite from Enfield Produce in Sydney. They will ship but have no idea on cost, and can you do so to WA?

Ken

Just had a look... one bag of Diatomite $35 plus shipping to WA $53... total $88 for one bag. Not an option methinks. I think I will pursue my current train and see where that leads. So far, the Zeo-Clor and/or Zeolite options with course grit are very promising so the next test will be something more temperamental.

Wayne

[Pup]

If you join the Bonsai clubs in WA you will be able to get Akadama and Carnarvon river sand. By the bag at reasonable rates.

Cheers Pup

[63pmp]

Did you sieve any of the components used, or were they used straight out of the bag?

Paul

[Wayne R]

@ 63pmp... I sieved for dust, of which there was a lot with the Zeo-Clor. I used shade cloth as the mesh.

@ Pup... I have considered this and will in time apply to join, however my problem centers on distance and time. Nonetheless, I shall start the process.

Regards

Wayne

[treeman]

I've read much on the internet and in this forum about the benefits of inorganic potting mixes. Unfortunately, my circumstances are such that I don't have access to nurseries other than the Blue and Green shed plus Coles, Woolies etc; I can't get hold of Akadama or any of those other exotic media. So what's a newbie to do? Grab what you can and experiment, obviously. I managed to source Zeolite from a cat litter (didn't turn to mush when wet), zeo-clor (alternate for pool filter sand) from the Green shed, scoria from local soil supplier (but this stuff is huge; about 15mm), course grit from the Blue shed and some standard potting mixes.

I needed a test plant and fortunately there are masses of a small flower appearing in my mum's garden that are as tough as nails (these things could grow on the dark side of the moon given half a chance) and three of them volunteered. I made up three different pot mixes and planted things up around 10 Sep 14. Each plant received Miracle-Grow weekly and the same amount of water each day. I stopped the test today to see how the plants fared.

Scientifically pulling each plant by the scruff of the neck out of it's pot I was amazed at how well two of the subjects had grown. A quick shake-off of remaining media showed the root development. I'm stunned and now convinced that inorganic soil mix is not only the way to go, but can be done cheaply and with readily available components.

Here's the results:

Mix A (not a success)
1.5 parts Scoria (about 10-15mm)
1.5 parts Course Grit
1.0 part Zeolite (>= 5mm)
0.5 parts Orchid Potting Mix

DSC_6826.jpg

Mix B
2.0 parts Course Grit
0.5 parts Zeolite (>= 5mm)
0.5 parts Premium Potting Mix

DSC_6824.jpg

DSC_6829.jpg

Mix C
1.0 part Course Grit
1.0 part Zeo-Clor
0.5 parts Premium Potting Mix

DSC_6825.jpg

DSC_6828.jpg

I found watering this mix far easier than with standard potting soils and am blown away by the root development. It's inorganics for me from now on.

Just curious. You say it's inorganic for me...but which of these mixes is inorganic? Mix A contains bark and mix B and C contains premium potting mix? (composted bark with all nutrients added according to the Australian standard) It's only natural that B and C performed better. (epecially in relation to iron availability)

[Wayne R]

I agree Treeman that my interpretation is liberal. Old habits demanded that I include a small quantity of organics but I don't think they contributed much to the result as far as root structure... could be wrong.

[treeman]

There is absolutlely nothing wrong with using totally inorganic growing media. But you must be aware of the beneficial properties of organic materials (humus) or of clay (akadama) and try to replace them somehow.
Humus and clay contain colloids (extremely small particles with a huge suface area and usually negitivly charged) which hold on to your cations (Ca+ K+ Na+ Mg+ and ammonium etc.) and release them as the plant needs them. Inorganics do not have this property (apart from the zeolites) so you MUST supply all the nutrients and keep them coming or your plants will suffer deficiecies. Hydroponics is a good example of this. They use substrates with a low Cation Exchange Capacity but supply nutrients in a constant stream and get great results. So if you are going totally inorganic you should include zeolite at 10% to get the CEC or feed very carefully (slow release) as whenever you water, the cations will be leached out. You can also get wild pH swings without the buffering capacity of colloids.
That small amount of potting mix you used will make a big difference.
But if you get the feeding and pH part right you can get fantastic results.