AusBonsai

Hi All,

due to the lack of supplies of Maidenwell diatomite around sydney, I'm thinking to replace it with Perlite. I've done quick comparison between the two, it seems that perlite might even be a better product. following is the brief comparison between the 2. since these are only fact, I would like to hear your real life experience for these products, especially for someone who has used both product for afew years.
Perlite vs mt. Diatomite
1. PH: perlite is neutral ph(ph around 7), whereas diatomite is more alkaline around 8-9.
2. perlite will hold more water, water holding capacity is >200% whereas mt sylvia diatomite is around 100%.
3. handling of perlite is likely to cause less health concerns according to this link. not sure if Mt.Diatomite is Diatomaceous earth, but I think it's similar.
http://www.google.com.au/url?sa=t&sourc ... -wVLyxykQQ
4. perlite is lighter which might be good for some. but I find it annoying because they float to the top during watering. workaround is to have top layer of something heavier(e.g. scoria, pebbles, zeolite....)
5. longevity? not sure, above article implies it might be longer, but the real material is softer than diatomite. so perhaps forum members could share their experience.
6. prices. the cheaper I could find online for perlite is 42.50$ for 100L which is cheaper than diatomite from enfield. $21 for 35L.

so Please have your say and share your experience.

the following is my intended mix.
2 part perlite
1 part zeolite
1 part course river sand.
optional: 1 part composted pine bark or peat moss depends on what plants.

Regards

Hi Cutejai,

All I can say is be carefull when you use Perlite. Mix it in a well ventilated area (outdoors) as you don't want to breath in the dust!! Wear a dust mask.

Regards,

Hiya cutejai. I haven't used diatomite due to lack of availability here but from what I have heard it holds it's structure while holding water, where as perlite holds water well but crumbles easily so after a while or rough handling (like chopsticking into the pot) it can become a fine powder.
I have found that aquatic mix from the big b is a suitable substitute to the diatomite I think. Another one I'm trying is lavalite kitty litter which seems very similar to the aquatic mix .
Hope this helps maybe some of the more experienced members can give you some more info

I did a mix of 50% perlite and 50% crushed brick and it is a bit hungry; ie you need to feed well.

Your mix also sounds a bit hungry.

I think the Mt Sylvia Diatomite would be preferable to Perlite and longer lasting.

Grant

Chris. Thanks will do.
Mugen: yes that's the only concern I have right now, abit crumble.
Grant: I saw your post re the crushed brick/perlite. it's looking good.
I notice your mix in the growing media test. seems like the following is the best combo. unfortunately you don't have any combo test with perlite except crushed brick. otherwise it would be very interesting and might even reveal if the PH level of Mt. Diatomite is negligible.
Maidenwell Dia 50% / Zeolite 10% / CRG gravel 20% / Coco Peat 20%

I might run a few test comparing the 2, since noone has really done any extensive test on perlite yet.

More input please forum members. I would like to hear experience from members who have used perlite and in what mix?

I only use perlite for prop. It's too lite, gives up its water too easily, causes just as many health issues as the diatomite and the pH isn't an issue when we fertilise a lot anyway. I can't see any advantages to using it other than price, and if i wanted something cheap, id just go back to composted pine bark and sand. I think it would work better and be cheaper than the mix you propose, though still not as well as the diatomite. Diatomite is amazing. Don't doubt it!

Joel