This may be more of a landscaping question so forgive me in advance.
I’ve got two things. Tons of Maryland Clay in my backyard and several scraps of drywall.
I was planning on renting a tiller this weekend and have heard that gypsum can help break up the clay. Is there any reason I shouldn’t use the gypsum in my drywall scaps and throw them in fron of the tiller?
Thanks,
JNF
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Replies
Non at all, go for it. Gypsum helps lower the soil pH cause it's a salt of sulfuric acid (CaSO4.xH2O) and performs same as if adding sulfur to the soil. However, if your soil is already acidic then grinding up the gypsum will only make it more acid and that could be bad for your garden. Before doing it, get your soil tested to be sure it would be beneficial to lower your soil pH. Adding amendments to soil while not knowing where your soil is at now is kind of like shooting in the dark. Same rule applies to treating swimming pools, you should test the water before you treat the water.
Dissolving gypsum in water won't change the pH. As a salt, it only forms ions and neither generates acid or base (See reaction "I.")
I: CaSO4•2H2O + excess H2O becomes Ca2+ + SO42- + CaSO40 + excess H2O and vice versa.
A common misconception here is that the water would be hydrolyzed to give off H+ and OH- ions which would then form H2SO4 and Ca (OH) 2. Actually, sulfuric acid and calcium hydroxide instantly react to form ions of calcium, ions of sulfate and water.
As gypsum provides both the calcium and sulfate ions, it can be used to remedy a soil deficiency of either. Soils deficient in calcium generally also have a low pH. The pH can only be corrected by adding a proper "liming" agent such as calcium carbonate. Applying gypsum to this soil will also supply the calcium but will not affect the pH.
Most clay compounds are mixtures of Kaolinites and Montmorillonites that both have long chain molecules. The sulfates resulting from mixing gypsum in the soil break down the long chain molecules into shorter chains and causes the soil not to stick or clump together as much.
PlaneWood by Mike_in_Katy (maker of fine sawdust!)PlaneWood
I have run scraps of sheetrock through my brush chipper prior to incorporating them into the soil. It[ the hammer mill/ chipper] seems to work quite well. The paper disappeared rather quickly.
If you're not adding any organics such as peat moss, ground bark etc. you won't be getting to far with the clay. Then again I'm assuming you want to make the soil arable...
Get the soil analysis. It will tell you what you need to add and in what amounts.
mix in sand...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Forget the primal scream, just ROAR!!!
Think of clay as cement and sand as the aggregate.A great place for Information, Comraderie, and a sucker punch.
Remodeling Contractor just outside the Glass City.
Quittin' Time
it works...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!<!----><!---->
Forget the primal scream, just ROAR!!!
With this clay here the sand would only stiffen the mix. No breakdown or loosening at all. I've tried it on one end of the horseshoe pits. One pit good, the other hard everytime it dries out. Gypsum has been mentioned around here as a breakup additive.
I "flatten" my ground around the perimeter with brick, tile and plaster. Never tried grinding up and filtering in drywall.A great place for Information, Comraderie, and a sucker punch.
Remodeling Contractor just outside the Glass City.
Quittin' Time
we just mix in coarse construction sand... add more till it stays looose...
may be a world difference in clays...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!<!----><!---->
Forget the primal scream, just ROAR!!!
I thought drywall had lime in it . Never knew any different .
Since Im a drywaller of the past ;
I used to sell the scraps to gardeners. They would in turn carpet the garden with them . Let it rain a few times on it and till them in. Tomatoes always do well here doing it .
Tim Memphest 2006
November 18th
never did gyp in the soil as it's done here..
this all new to me..
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!<!----><!---->
Forget the primal scream, just ROAR!!!
Edited 9/28/2006 8:09 pm by IMERC
I dont know jack about where you live either .
I only been there once and it was somthing like 15,18, feet of snow er somthing like that. Steam Boat Springs.
Somebody said the snow actually left for summer but I dont know.
I dont really grasp gardens there like here. <G>
Tim Memphest 2006
November 18th
the snow almost left... almost...
gardens here are a 24/7 resturant for all the critters...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!<!----><!---->
Forget the primal scream, just ROAR!!!
Soils vary, but I'm writing to share a neat mnemonic I read in a gardening book years ago. It is a way to keep soil amendment strategies in memory, and it goes:"Clay into sand, money in hand. Sand into clay, throw money away." The idea being that a little clay can remediate sandy soils that drain too well, but large amounts of sand will not improve clayey soils that fail to drain. FWIW.Bill
gtot it....
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!<!----><!---->
Forget the primal scream, just ROAR!!!
OK Doc, now whatcha got for me? I think I need to find my glasses. I read "extra drywall to break up my day" and stepped into a muddy thread
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Glasses are good things. It's my CLAY.Bill
I read somewhere that gypsum does something with the bonds that hold clay together and using gypsum will make it less "sticky". I had good luck with composted leaves to loosen the clay in my garden and I also broke up old drywall and threw it in with the compost. On my lawn I had pretty good luck with dolomite pellets, IIRC.
Think of clay as cement and sand as the aggregate.
Oh, come on. That's just untrue. The only way you get a concrete-like result is if you're fool enough to dig clay while its rather wet, and don't break up the chunks properly while working it.
I grew up in central Iowa - land of the black gold soil, deep as a man is tall. Then I moved to eastern Nebraska. What a change - mostly heavy brown clay. Bleah. Fortunately, it responds well to amemdment.
There are two tricks with adding sand to clay...
1. Use a sand that is coarse. Fine sand is basically worthless for amending clay, unless you add immense quantities.
2. Use a LOT of it, and incorporate it very well. This is the problem - especially in heavy clay, it takes so much sand that it's easier to just dig the stuff out and use it for fill somewhere else, then replace w/ a mix of compost, black dirt and sand. That can get quite expensive if it's a big area, however.
Jason
Its not untrue jason. Cement and sand without water is loose. Add water, let dry and you've got sand mix concrete. Same thing with this clay along the Maumee valley. Coarse sand? Mix stone in with this stuff and add water, damn near concrete.A great place for Information, Comraderie, and a sucker punch.
Remodeling Contractor just outside the Glass City.
Quittin' Time
I guess all clays aren't created equal...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!<!----><!---->
Forget the primal scream, just ROAR!!!
I agree with you, soils are different.
I can vouch for Calvin, the clay around here is ungodly.Remodeling Contractor just on the other side of the Glass City
I learned from one of the dit guys here when he did my driveway this past year - he mixes a small amt of clay to the sand/gravel for driveway toppings. Before, it would pothole and wash out the fines. This past year since he did this, it is harder and stays in place. Only one small pothole the size of your hat in the whole quarter mile run in. of course this has a lot to do with base fill too, which I had already done, but I was impressed. Don't know if it would would with Colorado choices of soils...
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Why not concrete it?
Quarter mile?
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Is that all the reaction I get? :-) lemesee... 5280/4=1320x10' wide = 13200 sq ft x .33 thick = 4356 /27 = 161 yds x $100 a yd = $16k for concrete only. Add $500 for form wood. Now import some southern concrete workers @ $45 a yard = $7200 and it all adds up to only ~ $24k or so. Should be no problem with all that $$$$ you make :-) Or, if you wanna go turnkey I got some guys who will do it for $2.70 a sq foot which would only be $35k!
every body here mixes coarse sand wit the clay on a regular basis...
The gardener...
landscapers...
semms to work... water draind and the CC effect is toned down a notc or two.....
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!<!----><!---->
Forget the primal scream, just ROAR!!!
Edited 9/30/2006 10:18 pm by IMERC
.......Until you add water again.Then yer back to quicksand-like clay again.FWIW, I added quite a bit of drywall to the clay in my driveway, and it doesn't seem to have made any difference at all.
You can never get ahead by getting even.
Yeah, Portland cement IS a type of clay
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
well then there you have it.
They "mine" for cement north of here across the Mi. border.A great place for Information, Comraderie, and a sucker punch.
Remodeling Contractor just outside the Glass City.
Quittin' Time
Here is the thing about amending clay soil. It takes tons of ammendment to make a difference - as in dump truck loads. If you have some drywall scraps to get rid of - fine - throw it out there, let it get wet and then till it in. It won't do much unless you have a LOT of drywall and a relativly small area to ammend. It might save some time over going to the dump and is a more "green" way to dispose of the scrap.
Edited 9/30/2006 2:11 pm ET by Matt
This is defiantly not "a one size fits all" question. With a BS in soils I thought I should respond; but did a quick refresher on the net and found that what applies in the upper mid-west may not only be wrong but counter productive else where in the country.
1) As mentioned elsewhere, gypsum does not effect the pH of acid soils. It has no significant effect on pH. To lower pH on acid soils use elemental sulfur or aluminum sulfate.
2) Gypsum will add sulfur and calcium to the soils. This may be of benefit in some area but harmful in others such as some western soils that are already high in calcium. By the way most mid western soils have no deficiency of S or Ca.
3) Soils high in calcium are known to immobilize phosphorous (P) in soils making the P less available for plant growth. Not likely a problem in non field crop situations. But adding gypsum could have that effect
4) Gypsum itself does not reduce soil compaction or increase water & air porosity in clay soils. Nether does adding sand.
5)The way to improve clay soils is to incorporate organic matter which serves 3 functions: a) it physically separates the soil particles so they can't stick together. b) it provides wick like channels for moisture to move thru the soil. c) it provides temporary exchange sites that hold soil nutrients (and moisture) then release them to the plants roots ( this exchange issue is not generally a factor with clay soils where the clay itself has this same capability; but it is a reason to add mulch to sandy soils which do not have that capability).
In short you are probably doing little good or harm by adding the gypsum to the soil but check local area extension offices if you are uncertain.
If you have a problem, don't just talk do something to set it right.
Jim Andersen
Edited 10/1/2006 11:00 am ET by jimcco