I have used a similar product purchased from Walmart. Like the product says, 'ABSORBENT'. And that is what it does... holds water. I screened it... washed it and still had sludge and mix staying wet for days. This is only my experience. Others may see things differently. I will be trying a different product called PermaTill. It is made by Stalite. It is a fired slate material; light weight and not terribly porous.

Here is a link that might be useful: PermaTill

This post was edited by bikerdoc5968 on Fri, Jan 9, 15 at 10:56

Bikerdoc:
thanks for your response =)

After doing GW searches and reading endless threads that argue the validity of using such ingredients, I think I'll hunt down the pumice.

One would think it would be easy to get here on LI (Dry Stall) where it's not unheard of to keep horses.

I'm hoping it's easier than getting turface =P

The only other option I have is the oil-dry, which I think doesn't perform as well as turface. Don't know though, have never been able to lay hands on it to try.

The sludgey stuff in the pots are a real bummer. I have a love-hate relationship with gritty mix that has more to do with sourcing ingredients than it's performance.

I guess if the Agway distributor in Hicksville (funny name for a town, right?) can't land me the goods, I'll try a quarry for horticultural substitutes like pea gravel sized volcanic rock.

NAPA part #8822 is what I use. The same as the pic above.

Rob

Rob is correct. part No. 8822.

I've used it for years in the garden.

dave

I don't know about the Napa product but isn't the 'Oil Dri' the same thing as clay kitty litter?

Don't know if it is the same as clay kitty litter as I don't have cats and have never seen kitty litter. This is what I purchased as "Oil Dri".

Hooki - keep in mind that the word "pumice" is a lot like the word "paper", or "liquid" - broadly descriptive. Pumice is a material that was spewed out of a volcano under a range of conditions that produce this soft, porous rock. As such, there is going to be a significant difference, chemically and physically, between pumice from variant sources. Some will be great, some not so great.

Al

Calcined DE shouldn't break down into mud. I think the problem with any product marketed as "oil dry" is that the technical specs are not specific to horticultural needs, and the properties can vary widely. Might be how you ended up with sludge in your pots. The DE either wasn't fully calcined, or possibly contaminated with clay filler.

Speaking of clay: Kitty litter isn't calcined - isn't hardened by high firing - and will turn to root killing mush.

Al has it right regarding pumice. The term "pumice" refers to the foamy structure of the stuff - NOT its hardness or composition. Much of what is sold for potting/horticulture is so soft you can easily split it with your thumbnail, and is so alkaline it will quickly raise the pH of the potting mix. The softness means some of it breaks down into fine sand in your pots. The alkalinity means it can cause nutrient lockouts in your plants.

The composition of pumice is basically alkaline feldspar. It gets its pumice structure by the way it exits a volcano. As you can imagine, the stuff that comes out of a volcano varies, depending on the mineral composition of the rock it melts through on the way to the surface.

Here in the U.S., a company named Hess mines a pumice deposit that is nearly neutral pH, at 7.2, and with a good hardness. Their product is used in scientific, industrial, and hydroponic applications. They also produce a landscaping product called Hort-I-Lite. I've yet to find a local distributor in my area, but if I were to use any pumice, the Hess Hort-I-Lite product is the only one I would consider.

I just bought a few bags of 8822... broke down almost immediately when wet.

Floor dry has always been fine for me. Maybe quality Control problems ?

http://forums.gardenweb.com/discussions/3211677/does-pumice-interest-you?n=134

I planted some plants in a mix with the oil dry from Walmart and it hasn't broken down that I can tell. Now I'm going to have to go pull something up to check..

In a spirit of cutting expenses to increase profit, makers of oil dry and kitty litter products could easily, it seems to me, switch to product that breaks down easier but still gets the primary job done more inexpensively. I'm not sure it would ever occur to them to consider the needs of gritty mix gardeners. The same goes for my chicken grit- I worry they might start to cut out some of the granite in favor of another component that is harmful to plants, if it suits the bottom line w/o harming chickens. They very likely don't know bonsai from banzai, crested cactus from crest tooth paste.

I am swayed more these days to switch from 'cheap and local' to components specialized to my growing. I don't want a plant I have been caring for for ten years to die in a mud bath or from a toxic component.

Good thread.

ez

Todd and EZ - I think y'all are on to something.

My first couple of bags of NAPA oil dry worked well for me. The last bag resulted in some sludge - here it is stuck in the bottom of the pot. I had noticed the pot kept leaking a white substance when watered.

In the oil dry's defense, my pots are outside all year long so it probably breaks down more quickly for me. The latest bag seemed to have a lot more fines, too.

It's not unusual for a company to buy what is supposed to be the same product from two different sources and have both products admirably serve the same purpose, even though they are slightly different - roughly the same thing Breathnez said above. One company might fire their product at higher temperatures, which would make it more stable than company #alternate. Whenever you plan to use a product the properties of which might vary, you should put a couple of tablespoons in a plastic glass or other unbreakable container with plenty of water and put it in the freezer overnight. If it's still structurally sound after it thaws, it should be ok in your media if absent any other phytotoxic additives.

Al

Ez - My comment isn't about oil dry, but my local feed store grit bags are specifically labeled as white granite. As long as they stay like that I'm happy!

ewwmayo, who knows if they might start mixing in crushed sea shells- that wouldn't be good for many plants, ok for chickens. I guess if it says 100% white granite...

Al, are you saying to perform this test dry, or wet?

ez

Ez - The bags do say added calcium, but not what the calcium comes from. Probably eggshells or shells. I'll ask the next time I need to get some more. The grit can be a little powdery, so I rinse thoroughly.

So far I haven't seen any deficiencies or strange symptoms (although it may not be visible). We'll see if it crops up as time passes or is a non-issue because the added calcium is minimal.

For sure, grit made of oyster shells and the like would be very bad and is not recommended.

I will say a few months ago I bought some flook dry that looked more like turface. The particles were tan not white like they usually are.