Using Diatomite as potting medium - Page 2 - Orchid Board

ans.smile · #11 02-02-2009, 01:47 PM

Hi, diatomite contains a lot of plant silica. Plant silica is very necessary for plant health, and helps plants to have a greater resistance to illnesses and climate changes - eg sudden drought. Diatomite contains other nutrients, but you should use it with your regular fertilizer program. To be conservative, it holds water 150% and more of its own weight. The water and silica and fertilizer are slowly released to the plant. Various tests were done and a lot of very good results were obtained on plants other than orchids. As far as I can see, orchids were not officially tested. However, if you go to the Maidenwell Diatomite page, you will find at least 3 references of people using diatomite for orchids and having success with it

orchids3 · #12 02-02-2009, 06:22 PM

It makes me wonder - I correspond some with people
in Australia (Orchid growers) and have yet to find anyone that knows and thing about the stuff. Why is it better than plain old stalite gravel from the gravel yeard or leica or many of the other things that are sold - has any testing been done by anyone other than the people who sell it?

Leisurely · #13 02-02-2009, 09:12 PM

I use 1/3 each of diatomite, charcoal and fir bark and as Donald said, I don't see any real advantages to it's use either except perhaps less frequent re-potting.

I don't think it matters what you grow orchids in as long as you provide the right amount of light, nutrients, air and water. I am currently toying with a few plants growing in rubber tire mulch. After three months, they look good but I am thinking that there is possibly something in the mulch that might be toxic.

orchids3 · #14 02-02-2009, 11:29 PM

Hi,
I have used rubber tire mulch mixed with CHC and dont like it. Someone else might.

Buds! · #15 02-03-2009, 08:22 AM

Well, I have been using diatomite (40- 50%) and sphag for about 6 months for phals, and it has been really good my growing conditions.

Previously, I have failed using 100% sphag, so after reading Albert's culture tips:
http://www.greenculturesg.com/articl...albertphal.pdf
I decided to give it a try.

I have half of my phals in s/h and half in diatomite/ sphag. They are both doing very well.

Sphag/ diatomite mix is a more gentle mix if the plant is in distress (ie store rescues), i also like it because it is easier to prepare when I am running out of time.

It is also easy to water- when the top layer of sphag is crispy and the diatomites makes a hissing when in contact with water.

Some people are concerned with the salt built up in diatomite, but it doesn't bother me because diatomite is cheaper than good bark here in West Aust. So when it is time to repot, I would just use fresh mix.

That is my 2 cents!

ans.smile · #16 02-04-2009, 12:57 PM

Hi, diatomite does not only hold water, it releases plant silica which is essential for healthy disease resistant plants.

Zildjian · #17 07-19-2010, 04:00 AM

Hmmm... I'm ordering a bag of diatomite (DE grade for pest control) as a natural plant & household pest control... is this the same diatomite being discussed here? If it is then it sounds interesting as you won't be having problems with pests & bugs. I have not tried it though and being a beginner still learning actually.

Ray · #18 07-19-2010, 11:17 AM

Quote:

Originally Posted by Zildjian

Hmmm... I'm ordering a bag of diatomite (DE grade for pest control) as a natural plant & household pest control... is this the same diatomite being discussed here? If it is then it sounds interesting as you won't be having problems with pests & bugs. I have not tried it though and being a beginner still learning actually.

No.

The diatomaceous earth you use for pest control is a fine powder - the individual diatom "shells" are very pointy, so it discourages some pests. It's particularly good for slugs and snails, as it cuts the foot.

Diatomite, as was said above, it the crushed, calcined (fired) mud of ancient freshwater diatoms, so it is in relatively large chunk form, suitable as a potting medium under some conditions.

Apparently the Maidenwell Company in Australia - the source of diatomite as orchid medium, is no longer producing it.

OrchidSue · #19 07-19-2010, 11:42 AM

Quote:

Originally Posted by orchids3

Hi,
What does diatomite provide to plants that other media does not provide? Is it not just silica based rock that maintains some predetermine amount of water? Is it heavy to ship? Have been wondering what the attraction to this one is.
Orchids3

It is inorganic, so doesn't break down. The claim is that it also provides silica as a nutrient to the plants. For my Paphs I use the mix that claims that it cannot be overwatered lightened up with a little additional perlite and the plants seem to love it. So, it seems to work well for my conditions. Always experiment with a couple plants before switching them all over to a different medium.

Susan

Zildjian · #20 07-20-2010, 12:31 AM

Quote:

Originally Posted by Ray

No.

The diatomaceous earth you use for pest control is a fine powder - the individual diatom "shells" are very pointy, so it discourages some pests. It's particularly good for slugs and snails, as it cuts the foot.

Diatomite, as was said above, it the crushed, calcined (fired) mud of ancient freshwater diatoms, so it is in relatively large chunk form, suitable as a potting medium under some conditions.

Apparently the Maidenwell Company in Australia - the source of diatomite as orchid medium, is no longer producing it.

Thanks Ray.