I'm guessing this kind of topic has come up a lot... you might consider using the search bar to find previous discussions of this topic.

I would not use coarse gravel (like they use for road beds). This is okay for top dressing ground plantings or laying an underlayer in ground plantings for drainage. I would also not use pea gravel, either. Too large and round. I do like it for top dressing.

Getting back to potting medium... some people don't even like aggregate (the generic name for sand and gravel) as a container medium component because of its weight and lack of porosity.

I do use it. My favorite is called crushed rock or crushed granite or "grit". I buy an A-1 Grit #10 grit. They have different size grades. It's not that convenient to find... you can look for chicken or poultry grit at feed stores. The cheapest is probably from roofing companies or roofing supply stores. It's not typically available at big box retailers. You might also want to look for "Sand and Gravel" vendors in your area: example in L.A. / Riverside area is Sunburst Decorative Rock.

More popular as a general-purpose aggregate and primary potting medium component is pumice (less popular but still often used is heat-treated volcanic rock called perlite). Look for recent posts on these products. In some areas, you can buy pumice at OSH or other garden stores. Unfortunately, you can't in my area of Los Angeles.

Pumice is also available at feed stores as "Dry Stall" for horse stalls.

Similar to pumice but retaining more water are calcined earth products such as garage-floor cleanup products (Napa 8822 of much recent discussion) and Turface (some people love it, others think it stunts cactus and succulents).

The very best source of information is club members in your area. They will have some idea of what is available in your area and works in your climate. Clubs are local affiliates of Cactus and Succulent Society of America (CSSA) which you can find on the website, Cactus and Succulent Plant Mall or on the CSSA website.

I guess we should make an FAQ or something, this question seems to come up every week or two.

Always great information from amanzed. Is there any way to make these kinds of basic facts threads stickied? I find myself wanting to reference them and having them permanently at the top of all threads would be lovely.

Moderators? Oh, Mods....?

I'm not sure this forum has those kinds of features. :-)

Amanzed, WOW!!! that was great .

I use Al's gritty mix, or a variation of it. I have some of mine in the straight gritt mix, with 1 parts each of turface MVP, #2 cherrystone chicken grit, and pine park fines. All a screened for optimal size. However, I've recently been leaving out the pine bark, and using a 1:1 of grit & turface. I pretty much use this on everything now, even tropicals, although I go 2:1 turface to grit for the more moisture loving plants. I have not heard of turface stunting anything, and would like to hear more on that. I can say from experience though, that everything I have in these gritty mixes is doing excellent.

Joe

You can take that gravel meant for concrete and pass it through mesh of various sizes (a process called "screening") to get more use out of it. You can just buy lengths of welded-metal mesh in 1/8", 1/4", 1/2" mesh widths (available at home improvement stores) and aluminum window screen material. Shake your gravel-for-concrete through these different size mesh and you'll have screened aggregate you can use for different cactus-and-succulent purposes. It'll be much more useful than the stuff you start with.

Ok, so bookmarking it is, amanzed. ;)
But if you can pull strings, see if making stickies is an option. Man, would that be sweet.

Mama Z,

Since you've asked, you're now the Committee Best Chairwoman for Increasing the FAQs - how's that for delegation?

Here is a link that might be useful: Yes, these are all there are, sadly

Amanzed,
Great information! Wouldn't a rounded aggregate allow more air and drainage than a sharp aggregate?

Wire mesh is more traditionally known as "hardware cloth." But don't ask for that at HD or Lowes unless you want to get blank stares :)

-R

Crap, land3499. I hate the blank stares at HD and Lowe's. Watch what happens when I go in and ask them for a diamond bit to drill through the $1 teeny ceramic planters (they call 'em ice cream dishes) I bought at Target.

cactusmcharrism, wow, I'm on The Board?! That was fast! What does a boardwoman need to around here to get some STICKIES???

ETA: Just clicked on those sad FAQs you linked to cactusmcharris. Ooof. No wonder you need to repeat everything. I hope you're linking from a pdf or a word doc you have saved for schluppy newbies like me.

Hi Robert: Well, I think it was someone's reasoning that rounded aggregate tends to pack more densely for the same screen size, but I haven't tested it. Just repeating hearsay that stuck in my head.

To test that hypothesis, we could just fill two containers to the same volume -- one with sharp aggregate, one with rounded -- and then measure how much water it takes to fill each to the top of the volume.

I suppose the geometry of the grains might have other effects on root growth having to do with root growth patterns... or the surfaces of sharp aggregate might just be rougher, improving beneficial biofilm formation. Or... it could be a silly, non-scientific Horticultural Myth -- as you've pointed out before, our hobby abounds with them.

And LOL... I think my Home Depot DID turn out to know "hardware cloth" in 2009 when I bought mine. Just luck at that location, I guess. I wish I could find 3/4", 3/8", and 5/8" mesh.

Mama Z,

At least one of those is positively swimming in joyous 'let me tell you about .....' verbiage - can you guess which one and why?

DC,

Hardware cloth's traditional sizes are 1/8" mesh, 1/4" mesh and 1/2" mesh - when I was in the hardware business, those sizes you cite were not made, but, OTOH, everything's made somewhere.

Jeff: Yup, so I discovered. I vaguely remember finding some more exotic, niche screening sizes (rather than mass-market hardware cloth)... but they were more spendy. Then I lost interest in micro-managing my screening of aggregate.

DC,

Oh, yes, hardware cloth for NASA needs to be within 1/2000th of an inch in spec.

As my aggregate / top-dressing collection is not what it was, I too don't have the obsessive / compulsive behavior I had previously exhibited, but I still pull out the 1/4', 1/8" and window screen sieves to process a particularly pretty batch of decomposed rock.

Hey MamaZ,

What pls. does this mean "see if making stickies is an option"? Sorry, I just don't know some of the lingo you're using. Sorry, just trying to understand what you mean like "schluppy".

A sticky is a thread that is marked by moderators to stay at the top of the list for everyone to see. It's very common on other forums, but GW is pretty bare bones. We don't have any of the fancy features of other forums like stickies, instant messaging, text formatting, or an ability to edit posts.

Jeff cactusmcharris: Right about when my obsession was fading, I got a few search-engine hits indicating non-US metric hardware cloth might offer some intermediate sizes without going all the way to NASA-grade screens.