A question re Diatomite and attapulgite.

[NBPCA]

Hi all,

I have started the tests of the various potting mix components and one major difference has emerged that I did not expect.

The two Diatomite(MaidenWell and Mt Sylvia) weighed about the same dry as each other and wet as each other. After draining they had both absorbed similar amounts of water as weight(about 90%)

However the Attapulgite was much heavier dry(about 75%) and wet than the other two, but had absorbed a lot less water(only about 35%) so that it was only 22% heavier than the Diatomites wet.

Has any body out there used both diatomite and Attapulgite and are there any noticeable differences in use?

Grant

[MattA]

Hi Grant,

I have not tried diatomite, still unable to find a source locally. As for Attapulgite I am intrigued by your results, I potted up a few test subjects, all of which died. While it looked dry at the surface & just below, it was actually holding alot of water between the particles at the bottom of the pots, am assuming thats why my test subjects died. Am now using it in trials 50/50 with potting mix, seems to be working alot better that way.

Look forward to more results as you come to them.

Matt

[bonsai4life]

G'day,

I've never used attapulgite as I was able to find diatomite( love the stuff)

But just recently I saw in woolworths LAVALITE by snappy tom, says its from south america I think.
Has anyone tried this stuff yet?

Cheers Gott

[Gareth]

Hi Matt,

Where abouts are you located?

I just purchased 2 bags of diatomite (maidenwell) from Queensland and only payed $30 in freight for both, i am located on thre Mid North Coast (port macquarie) so if you are around that area you may be able to get it for somewhere near that cost.

I used the startrack account at work and we get fasirly good rates, But david At Productive Gardens (the placed i purchased the Diatomite from) said he was going to look into using start track so it might be worth a shot depending on where you are.

Re the Diatomite, i have found it to be very free draining even when saturated, could it be that the attapulgite gets "boggy" at the bottom of the pot whereas diatomite doesnt?

I should mention my experience with diatomite is only very new, so this is purely only from limited observations since i have started using it.

Gareth

[Joel]

I have tried both and love the diatomite, hate the attapulgite.

Brett gets results with it, but i cant stand the stuff. It just breaks down into fine particles for me. It holds too much moisture down low, whilst the top dries out really quick. It cakes together and becomes rock hard.

Joel

[Grant Bowie]

I have tried both and love the diatomite, hate the attapulgite.

Brett gets results with it, but i cant stand the stuff. It just breaks down into fine particles for me. It holds too much moisture down low, whilst the top dries out really quick. It cakes together and becomes rock hard.

Joel

I can't yet comment on the performance of either, but thanks for your input.

Grant

[Grant Bowie]

Hi Grant,

I have not tried diatomite, still unable to find a source locally. As for Attapulgite I am intrigued by your results, I potted up a few test subjects, all of which died. While it looked dry at the surface & just below, it was actually holding alot of water between the particles at the bottom of the pots, am assuming thats why my test subjects died. Am now using it in trials 50/50 with potting mix, seems to be working alot better that way.

Look forward to more results as you come to them.

Matt

I am using all the materials graded into sizes, sieved of fines and dust, and putting the materials into layers. Coarse at the bottom, medium then fine.

I will vary and trial the ways of growing with the media once I get to the growing trials.

Grant

[Bretts]

Hi Grant
Best I can figure what you are saying is that the Attapulgite is heavier than the Diatomite and absorbed less water?
But I am unsure what your question is.
I generally used Attapulgite as an additive in my soils in the past maybe 1/3. Since so many questions where asked about it I potted up one pine seedling at 100% just to get a more concise understanding of it's use. It went fine as far as staying sound draining and all but has some serious nutrient deficiencies. Although this is not the only 100% medium that I was testing this happened with, 100% scorio was another.(might need a leaf out of Walters Recent article ) I am trying to remember to up the fertilising on it but I could have done much better. I have upped the fert better at the moment but it might be too late!
As far as watering goes all I can say is it gave me no issues. When it looked dry on top I gave it more. From memory this was every 1-2 days but once to twice a week at the moment depending on the rain
Oh and the one I have in Diatomite did need watering less often. about 2-3 days.

[NBPCA]

Thanks Brett,

I may have jumped the gun a bit. I have now expressed the amount of water held by the three products as the weight of the water held.
Here are some preliminary test results of just the diatomite and attapulgite.
Weight dry.
Mt Sylvia 2.7 kg
Maidenwell 2.65 kg
Attapulgite 4.65 kg
Weight wet but drained
Mt Sylvia 5.08 kg
Maidenwell 5.14 kg
Attapulgite 6.3 kg
Water held expressed as weight of water(not as % of weight of Material)
Mt Sylvia 2.38 kg of water
Maidenwell 2.49 kg "
Attapulgite 1.65 kg "

So the Maidenwell is the lightest and holds the most water
the Mt Sylvia is almost as light and holds slightly less water
but the Attapulgite is much heavier when dry and absorbs/holds much less water.

The texture and feel when moist of the 3 are very different as well. The Mt Sylvia feels almost dry to the touch after one hour, whereas the Maidenwell still feels slightly moist after a day and the Attapulgite feels very moist after a day.(Winter in Canberra.

Any how my question was simply. Has anyone used both Attapulgite and a Diatomite(not together of course) and how do they feel they have performed in any way as opposed to the other?

Grant

[Gareth]

That is some very interesting and useful information.

Looks like the maidenwell is coming out on top slightly but could be substituted with the Mt Sylvias if needed and the difference would be neglegable.

Gareth

[NBPCA]

That is some very interesting and useful information.

Looks like the maidenwell is coming out on top slightly but could be substituted with the Mt Sylvias if needed and the difference would be neglegable.

Gareth

I don't think it is as simple as that. It is just that the Attapulgite is behaving differently to the Diatomite. I feel more water is being held between the particles of Attapulgite (hence it feels wetter) whereas the diatomite is absorbing/holding the water inside the particle (hence it feels drier).

The grow tests will be the ultimate determinant of what works best for a bonsai mix/component.

I will do some tests growing in pure Diatomite/Attapulgite/Kanuma/Akadama/Crushed brick/Perlite/Pumice/Scoria/Zeolite/Blue Metal/Chinese Akadama but the ultimate mix will probably be a mix of components and I am especially after experiences of growing in Diatomite vs Attapulgite at the moment so I can devise some worthwhile trials.

Grant

[Bretts]

Any how my question was simply. Has anyone used both Attapulgite and a Diatomite(not together of course) and how do they feel they have performed in any way as opposed to the other?

The main difference I have found is that the Attapulgite breaks down over 2-3 years and the diatomite does not. Attapulgite may be influenced by the ph of the fertiliser/water you add more than diatomite but I still need to test this more to be sure.

[NBPCA]

Any how my question was simply. Has anyone used both Attapulgite and a Diatomite(not together of course) and how do they feel they have performed in any way as opposed to the other?

The main difference I have found is that the Attapulgite breaks down over 2-3 years and the diatomite does not. Attapulgite may be influenced by the ph of the fertiliser/water you add more than diatomite but I still need to test this more to be sure.

Thanks,

I'll add the freeze and thaw test as well to the list of tests. Another test suggested was the amount of water needed to get the entire mix wet and then then to start to run. A bit trickier to organise but I think it can be done with an inverted 2ltr plastic drink bottle.

Grant