AusBonsai

Hi just a quick question about soil components. I've got a big bag of aquarium gravel that I had planned on using as a grit type part of my soil mix but a mate of mine advised me he'd heard it was no good as it was rounded and had no sharp edges. I'd like to use it as it's just sitting there, and I probably will. So I guess my question is what are possible negatives effects I should look for. We're both pretty new to the game and most of our knowledge is based on random articles read on the net and he couldn't tell me why it was bad just that he'd read it somewhere. He's usually right but I can't see what the problem would be. (And I'd love to get a win lol) Cheers for ur advice in advance. Love this forum

And sorry just realised this should probably go in another section.

Hi Phil
Moved it for you

Years ago i purchased a tree in a grow pot from Koreshoffs and it had what looked like aquarium gravel in the pot as a coarse component.
Worked OK but was very heavy.

It certainly will not hurt to use it , but I have heard that the grit needs to have sharp edges to make the roots split and divide, but reckon that would be rubbish.
the rounded smooth surface would have less moisture holding potential though which is to me is a better reason not to use it.

I have used it a top dressing and as a gravel bed for my smaller trees to cope with the summer temps.

Ken

If you are using it for a drainage component in your mix then it would be but remember this, gravel (especially Quartz) has little to no moisture holding capacity with the exception of what sticks to the outside with surface tension and also provides similar qualities with respect to nutrients. The rounded/sharp edge thing is up to you.

There are one really good mix components around which you may know of but if not just lift the lid on this in a search. Inorganic mix or inorganic ingredients

If it's sitting around taking up space I would use it up mate, more space for trees

Ahh speedy Ken

Thanks guys. I've been looking for diatomite but can't find any here. Tried a couple bags of Kat litter and ended up with a bucket of mush when I tested it. Jsut had a look around and saw that a lot of people are using blue metal. This sounds worth looking into for me as I know it's available here but I suppose it's just got the sharp edges over the aquarium gravel. I have used perlite previously and my plants seem to be going well but it's just seems too light and doesn't "hang onto " the tree much in the pot. I use a pretty high amount of organic components in my trees as it gets pretty hot here in grafton and I'm not always home so my thoughts are I need a high quality inorganic compound in my mix. I've looked at some of the Scoria and stuff at the big shed but it looked too large. Is there a guideline or ratio for pot size to aggregate size? Or could someone post a pic of the size of inorganic components they use. I guess I've got it in my head that the particle size should be the size of the perlite I've used but I could be wrong

Give Mt Syliva a call or email. I think they will sell at the gate in small amounts.
As they are not that far from you maybe a day trip could be in order.

Delivery from Sydney is about $20 so for a few bags might be worthwhile.

Ken

Cheers mate. Will do. I've got a wedding to go to up that way in a few weeks.

phillicondor wrote:Thanks guys. I've been looking for diatomite but can't find any here. Tried a couple bags of Kat litter and ended up with a bucket of mush when I tested it. Jsut had a look around and saw that a lot of people are using blue metal. This sounds worth looking into for me as I know it's available here but I suppose it's just got the sharp edges over the aquarium gravel. I have used perlite previously and my plants seem to be going well but it's just seems too light and doesn't "hang onto " the tree much in the pot. I use a pretty high amount of organic components in my trees as it gets pretty hot here in grafton and I'm not always home so my thoughts are I need a high quality inorganic compound in my mix. I've looked at some of the Scoria and stuff at the big shed but it looked too large. Is there a guideline or ratio for pot size to aggregate size? Or could someone post a pic of the size of inorganic components they use. I guess I've got it in my head that the particle size should be the size of the perlite I've used but I could be wrong

Bunnings sell 10mm scoria which is good and bad for small trees that are growing.
Bonsai South in Caringbah has 2-3mm Scoria and I think it was $20 for a Bag. If thats the size you are looking for regarding perlite size? Give them a call and see if they do delivery.
Smaller size scoria will hold more water from what I've been told at Bonsai South

I'm also looking for Fine Gravel too from Landscapers but all I see are mainly pebbles with rounded edges and even if I find the right one, they are too expensive for a bag. Blue metal seems to be a good choice with beneficial nutrients from the rock itself and cheaper .

Have been using it for 30 years, we call it Carnarvon river sand, we buy it in bulk this has rough surface.
The trees sent from WA to the National Collection all had it in their mix.

Cheers Pup

Pup wrote:Have been using it for 30 years, we call it Carnarvon river sand, we buy it in bulk this has rough surface.
The trees sent from WA to the National Collection all had it in their mix.

Cheers Pup

Hi pup. Are u saying u use the aquarium gravel?

phillicondor wrote:

Pup wrote:Have been using it for 30 years, we call it Carnarvon river sand, we buy it in bulk this has rough surface.
The trees sent from WA to the National Collection all had it in their mix.

Cheers Pup

Hi pup. Are u saying u use the aquarium gravel?

The gravel we use is also sold in Aquarium shops, not the coloured stuff though.

Cheers Pup