None.
Instead, you mix in compost.

Some of the cat litter I have seen is made of expanded clay while others are made of ground up corn cobs. However, both need to be purchased form a store while waste organic matter, tree leaves, left over food, grass clippings, any vegetative waste, is generally available for free, your hauling it home. To get enough cat litter into that sandy soil to make any difference will be quite expensive, requiring probably around a ton of it depending on the size of the garden.

Kimmsr's knowledge of kitty litter is incomplete, lol! Some brands are made of diatomaceous earth, which is what the poster is referring to. It makes an excellent potting soil amendment, but pretty useless as something that will improve your outdoor soil.

There are also some calcined clay cat litters, pretty much as hard as Turface, that make very good additives to a potting medium. Those are very different from the soft clay litter familiar to most. Still not practical for use in situ, in the garden.

As suggested, the regular addition of a combination of brown or green ingredients is what will help any kind of soil over time. Wood chips, pine bark, municipal compost, fall leaves, etc., can be added. Even the simple act of using a mulch composed of these and other organic components will find its way into the soil where it can do a great deal of good.

I have a couple of loads of fresh wood chips delivered to me each year, at no cost. I have very dense red clay soil that somehow supports a healthy population of hardworking earthworms. They do all of the work of pulling the chips into the clay.

I wish I could offer some advice but living on heavy clay, I know a lot more about adding sand to clay than the other way around!

For a small garden, if this stuff really works, it might be a fine idea to adjust the particle size balance of your soil. I will not totally dismiss the idea but do use lots of compost at either way.

If you want to learn more about this particular cat litter brand, you should try to find some local gardeners who have used it. Just doing a quick search I can see there are at least 3 kinds of Coles cat litter so you'll have to make sure which one is intended.

Do let us know how this works out.

Thanks all for your responses, they've been very helpful.
I was interested because I saw on other forums that people had used this in their outdoor soil but I have pot plants as well so I may do a test run with something and see how it fairs.

and lol, thanks toxcrusadr-- that's a good point. I may have to go to the shops and read the bags to see what's exactly in it.

Hi fellow Sandgroper, all your specific questions about WA soils (and clay) are addressed as per the attached link....its very informative.

Here is a link that might be useful: WA Gutless Soil

Potted plants generally need a potting mix specially formulated for pots, and it usually doesn't have soil in it.

I thought that i rembered watching a video about a guy in Aus. puting clay in his garden. At the 8 min mark he talks about puting in bentonite. I rember at the time thinking it didn't look like he was adding all that much. Any way it looks like adding bentonite to sandy soils does improve them and is standard practice where you are. Read antipodeans link and learn all about it.

So does any on in the states add clay to thier sandy soils? Or is this more of something they only do in aus? from the aus links it looks like it is easier to add clay to sandy soils, than it is to add sand to clay soils.

Here is a link that might be useful: Permaculture in perth

I add regular clay kitty litter (the cheap stuff, no additives) to my very sandy soil with good results. It takes about a year to see them though, because almost the whole place is sand, so I just throw it out there, and layer it with pine fines.
In about a year, I begin to see plant life in those areas.
It's what I call 'My sacrifice to the Lawn gods'

This post was edited by MsMorningSong on Sun, Jun 22, 14 at 0:16

Adding a small amount of clay to a sandy soil does little or nothing, one would need to add a very large amount to make much change. If that kitty litter is made from ground corn cobs then you are adding organic matter, but unless you add several pounds it will not do much and can get to be quite expensive.
Organic matter is what soils need for improvement and much of it is available free.

I thought about this a lot, and I tried it but it was more like a soil unimprover. It makes your soil worse.

TheMadHippie....don't know if you have pot (marijuana) plants, potted plants (plants in pots) or potted pot plants?
Nancy