Decomposed Granite

[Greenleafs]

Hey, does anyone know where I could get some decomposed or crushed granite in Orlando, Fl? Maybe delivered?

[rpw]

Call a landscape rock company:
crushed granite | Granite in Orlando, FL - YELLOWPAGES.COM


Peyton

[amanzed]

Might as well continue this thread for Los Angeles area.

Anyone find a good source near L.A. for crushed granite? I have bought "decomposed granite" separately from Throop (by the bag) and from Rustic Stone (by the shovelful)--both in Pasadena--but I have not found a source for sharp, crushed (and maybe screened) granite.

I'd like to try something like the medium used by Huntington Botanical Gardens, which seems to be mostly 1/16" to 1/8" granite (by sheer guesswork). I asked at the Huntington, but the person I talked to wasn't sure where a member of the public could get such stuff.

For now, I topdress with 1/8" to 1/4" pea gravel (by the 100 lb bag from Throop). For the main medium, I screen out some of the fines from my decomposed granite (for rot-prone plants). Then I mix that with Perlite from OSH and Supersoil mix from Home Depot or OSH:

1 part decomposed granite (screened coarse),
1 part Perlite (also coarse),
1 part Supersoil

I'd like to mix in some of my local soil, but it's mostly clay and I wonder about nematodes and other pathogens (even though I'd like some natural beneficials).

Any ideas?

--dean

[Allen Repashy]

If you need it on a small scale, try a local feed store's chicken grit. It comes in various sizes and is more a crushed granite, but works very well. Turface MVP is my personal favorite and also an excellent product to consider. I think it runs about ten bucks for a 50 pound bag. It is a highly porous calcified clay that will not break down over time or under pressure.

[Greenleafs]

I found some crushed granite screening at pebble junction. Thks for suggestions though.

[Steve Steward]

"Oil Dri" is the same (or very similar) to Turface, and is sold for around $8 per 50lb bag at ACE. I will say however, that Turface et. al. seems to have stunted the growth of everything I used it with. Very anecdotal - use my post with skepticism

[Matt Maggio]

Concerning the LA area, Whittier Fertilizer Co. (actually in Pico Rivera) usually has a decent grade DG for soil incorporation. The higher the clay content, the less you should use in proportion. You have to purchase by the half-yard increment however. For DG top dressing, I've made an escapade or two along Hwy 39 or the Angeles Crest Hwy road cuts... not that I really recommend it

[amanzed]

Thanks again, Matt. In the last couple days, I got another recommendation for Whittier Fertilizer (from the very helpful Brian Le in Northeast Los Angeles).

I tried a couple feed stores looking for crushed stone grit, but so far I haven't found plain grit -- only a composite "chicken health grit" with poultry-specific additives like eggshell or dolomite.

However, for anyone who's interested in crushed granite (1/4" and lots of other sizes), or decorative stone for top dressing, I've had four different people point me to Sunburst Decorative Rock in Irwindale (pointers again from the incredibly nice and informative Brian Le, also from Rustic Stone La Canada, Throop Sand and Gravel -- when they didn't have what I wanted -- and Bellefontaine Nursery).

--dean
DC Elzinga

[Matt Maggio]

I'll place a recommendation for Sunburst Decorative Rock as well... it's right down the street from Whittier Fertilizer.

Matt

[Ronald Chisum]

Crushed granite is frequently available at roofing supply companies. Usually they cary various grits by A-1 Grit Co. granite. Go to A1 Grit to see their products. The #10 grit is a great top-dressing and the #16 and #10 both make nice additions to a mix.
PS the chicken grit mixes with oyster shell are actually nice additions to a mix as they help add calcium. My main objection to the chicken grit is it is more expensive. Lots of luck. RON

[vapester]

sooooo, my agave and succulent collection is growing pretty quickly and i don't know much about this. Is this a preferred top soil for pots and ground plants ? And if I find it, a very small 1/8" is what to look for ?? I've been wanting to change to a nicer top dressing for my potted plants. I mainly just use fine orchid bark, tho one plant i did use crushed gravel. But i felt it maybe keeps the moisture in too long. There is an A1 or rock place near my house in Wilmington that prob has the stuff.

[Ronald Chisum]

Top dressings and soil mixes are worthy of their own threads. Ornamental dressings are frequently used on show plants. In my area, some nurseries use a lot of perlite in their mixes to insure good drainage. Perlite floats and will easily wash out of the pots. Rock top dressings prevent this washout while maintaining evan more rapid drainage near the base of the plant. I suggest you join a Cactus & Succulent Society if there is one anywhere near you. Members can fill you in on some of the best ways to cope with your particular needs. RON

[Addictedtoagaves]

I recently went to my local sand and gravel supply to inquire about bulk DG and they told me 1/4minus is the material I needed. It is basically whatever will fall through a 1/4" screen, the product I got is as heavy as sand but contains all different sizes of pieces, well 1/4" and smaller of course. It seems to be working out ok when I make a new batch of mix.

Anyone ever use 1/4minus instead of "decomposed granite" or did I discover what everyone uses already, on my own?

[Boo Hollow]

Originally Posted by Addictedtoagaves

I recently went to my local sand and gravel supply to inquire about bulk DG and they told me 1/4minus is the material I needed. It is basically whatever will fall through a 1/4" screen, the product I got is as heavy as sand but contains all different sizes of pieces, well 1/4" and smaller of course. It seems to be working out ok when I make a new batch of mix.

Anyone ever use 1/4minus instead of "decomposed granite" or did I discover what everyone uses already, on my own?

What you have stumbled onto is the terminology used for rock quarry size separation. 1/4- is really used as a sizing for crushed stone, regardless of type. Sometimes this crushed stone mix, along with the fines, is sold as DG, and used for paths, base fill material for pavers/bricks and other applications where it is desireable to have a range of sizes that allows for better compaction but good drainage. Like Matt mentioned earlier, some of these "DG" mixes have clay binders in them specifically for the compaction effect. True DG is a weathered by-product of granite that is decomposing and producing smaller and smaller particles over time. Remember that when you use a mix with quite a range of particle sizes that it will tend to compact and also the pore spaces will be smaller and thus the aeration quality is lower, the water capacity higher and drainage slower. Since most of the people I know whom use DG (the actual crushed stone product) in their mixes tend to focus on cacti, they rinse out the DG to remove the fines prior to use.

I use scoria, red lava rock, 1/4 - 3/8 in size with good results. I avoid mixing in the smaller fines that are sometimes available as a running track coating (cinders). For plants that are being grown for resale, I use perlite instead due to weight issues.

[madabouteu]

Let me add my viewpoint as a geologist. There IS a chemical difference between crushed granite and decomposed granite. Decomposed granite has undergone physical and chemical weathering, and the minerals have started breaking down, releasing the cations. Ferromagnesian minerals will more readily give up iron and magnesium, feldspars calcium, sodium and potassium, and so on. Here in northern Alabama, surrounded by sedimentary rock, I have no choice - crushed granite from the feed store is what I can get and is what I use! But when I visit the Piedmont area south of here, I try to scoop up the sands around the lakes in that area and incorporate those into my mix.

[Addictedtoagaves]

I bet the scoria you use is just as good or better than pumice as a drainage aid, it is so rough and porous. Most of the ornamental palms grown in Hawaii and imported to the states use the crushed lava rock in their mixes. (I bet they don't have to go far to get their lava rock )

While on the subject of crushed granite, I recently re-roofed my patio with torch down roofing and I have 3/4 of an 80lb sack of biege colored roof granuals left over, the bag states it is crushed granite and upon close inspection looks as if it is highly pure. It is very clean as nothing will wash out of it when rinsed. Can this material be used as a seed cover to help prevent damping off when using organic germination media or is it too course? I'll guess the particle size is +/- 1/32"-1/16" on average and is very uniform. I don't want it to go to waste if is good for something, it was reasonably inexpensive at $18 for an 80lb sack.

Keith

[Boo Hollow]

Keith - I don't see any problems with using this as a seedling cover. Most seedlings have such a hydraulic lift capacity that pushing aside a thin layer of this stuff shouldn't be a problem. I think in general, when we grow something from seed, we tend to pamper our seeds and seedlings too much and treat them as they are young infants struggling to grow up and need our constant and vigilant protection. This also flies in the face of millions of years of evolution. I always opt for the more "mother hen" approach than leaving stuff to chance, however I still marvel at just how robust seedlings are and how they seem to manage to proliferate despite some horrendous natural conditions. One just has to sit back and imagine how that agave or cactus seed penetrated the desert pavement and survived to itself, bear seed. Good luck!