Source for Diatomite and other mediums in Europe

[johnblagg]

diatomite should be avaliable at pet stores it is used as filter media for aquariums ...unless I am totaly off .which I may be as what I am refering to is a fine powder form.

[RosieC]

John, I read someone on OB only a few days ago saying... "don't get the aquarium version, it's too fine". So I'm guessing there is a corser version that can be used for Orchids.

Never seen the stuff myself, just one of those things that I remember reading.

[kavanaru]

Originally Posted by RosieC

John, I read someone on OB only a few days ago saying... "don't get the aquarium version, it's too fine". So I'm guessing there is a corser version that can be used for Orchids.

Never seen the stuff myself, just one of those things that I remember reading.

I remember having read that too.. but cannotfind the originalpost either...

[johnblagg]

LOL I kind of thought that myself ..

[chromebright]

the substance that has been mentioned in several posts above is diatomaceous earth........NOT diatomite.

diatomaceous earth is a powder and is used in aquarium and pool filtrations systems (as well as a cockroach killer) and is not appropriate for orchid growing AT ALL.

diatomite is rock of various sizes that is marketed under brand names of "Dyna-Rok", Higromite. It is excellent for semi-hydroponic culture. I have planted keikis from Den. kingianum in both LECA and Higromite, treated both cultures exactly the same in terms of watering, fertilization, humidity, light levels, and the higromite planted Dendrobium is at least twice the size of the LECA planted specimen. I will try to post photos of the two plants later today when I have time.

As far as sources for obtaining diatomite in the EU system, I can't help you there. Sorry.

[chromebright]

The Dyna-Gro website lists this source for their products in Europe: http://www.orchidaccessories.co.uk/

I looked that the orchidaccessories website, however, and did not see Dyna-Rok advertised. You may be able to special order from them.

Dyna-Gro is based in Richmond, CA, USA and their website is: Dyna-Gro

This is the Higromite website: Home Page

[RosieC]

I know that the guy at orchid accessories often does not list these types of items on his website. He told me the reason is that he feels the shipping costs for something like this is so expensive that he does not want to encourage people to buy it mail-order.

He generally sells media of various sorts at shows or will take it to a show for collection if someone has placed an order.

I can't confirm the Dyna-Rok specifically, but he does stock quite a few products not generally found outside the USA. I've spoken to him about S/H types of medium in general (no brand names) and he was very reluctant to sell me anything of that nature unless I was collecting it.

[glitchathon]

Originally Posted by chromebright

the substance that has been mentioned in several posts above is diatomaceous earth........NOT diatomite.

diatomaceous earth is a powder and is used in aquarium and pool filtrations systems (as well as a cockroach killer) and is not appropriate for orchid growing AT ALL.

i think diatomaceous earth (DE) and diatomite is often used interchangeably (and in fact describe the same ingredient) because calcined DE can often be rock-like and suitable size for plants, bonsai, and even orchids.

I have used Napa Floor Dry from the auto parts store, which is diatomaceous earth, successfully with tropical plants and about to give it a try with a Paph (probably will repot it tonight). It is cheap ($6.50 for a 20 lb bag). However, maybe 1/4 of it will need to be filtered out using insect screen or kitchen strainer to get rid of fines so it is more like $6.50 for 15 lb of useable material. The particle sizes after filtering is around 1/8" to 3/16".

The stuff is awesome for plants as it retains water, while staying well aerated and very durable as it is inorganic. It should perform nearly identical to Turface.

But yes, the aquarium and swimming pool stuff is totally inappropriate.

[chromebright]

here's a comparison of two keikis from the same Den. kingianum plant both placed into s/h in May, 2010.

the plant on the left is in PrimeAgra and on the right in Higromite . As described above, both receive exactly the same care.

Also note that some roots are growing out of the pot with PrimeAgra and no roots are escaping the Higromite.

Higromite was difficult to get awhile ago but it looks as though a new distributor has emerged and, although it costs alot to ship, at least it is more readily available now.

Ken

[chromebright]

here's a website describing diatomaceous earth....it says that the ungroundup substance is called diatomite ...Diatomaceous Earth

calcined DE seems to be superheated DE

As far as I know, products like Dyna-Rok II and Higromite are rocks made up of diatoms with varying amounts of volcanic material intermixed. I believe Ray Barkalow told me once that Higromite has the highest amount of volcanic material intermixed with the silica from the diatoms. The pieces of both these products are much larger than described for the DE products and therefore much more appropriate for semihydroponics.