Gypsum in your organic soil mix!

[Scrappy4]

Don't forget crab meal as a calcium source. It's one of those multi helpful amendments. It also provide chitin, that in turn attracts chitinase, a helpfull bacteria that eats bug parts along with the crab meal. Win win as they say.

I sometimes add some root powders between cycles as I repot too. I mix dandelion, nettles, and comfrey root powers and give 15 gallon pots about 3 oz of the mix about once a year, in the hole when I remove the root ball for replanting. Just more diversity and more calcium among other beneficial compounds.

 

[Scrappy4]

Oh I get the powders from rose mountain herbs.

 

[Speed Racer]

Thought of crab meal before for added calcium, but does add npk. Not sure how much and have to figure in with the nutes. Add some fish bone meal and more in bloom which has calcium too. The dandelion, nettles and comprey sound good and need to read up more on. Very nice. peace... SR

 

[moses wellfleet]

Its not Calcium Carbonate - that's always good for hardwater growers.

bigshrimp can you please elaborate on this statement?

 

[stoned-trout]

I use it all the time...yeehaw.. got a 50 lb sack I think it is..along with lime and Epsom salts..crab,shrimp,lobster ect all good and in my mix for sure..dandelion and friends in my compost and wormfarms..

 

[Witheridge]

Thanks. Useful info here.

 

[moses wellfleet]

What I was asking, can it be used with calcium carbonate/calcitic lime or is meant as a substitute for cc?

 

[Granger2]

Thanks, Scrappy. After more thought, I think I'll stay with my non micronized Gypsum. The micronized may dissolve too fast. Still observing. -granger

 

[Cep]

Moses,

You can substiture it for lime but that choice should be made based on what is in your soil already. How much Sulfur is in your soil? Like Coba said is supplies S. If your soil is really acidic it is probably lacking Calcium and basic lime will raise it.

If you don't plan on getting an analysis maybe just make your decision based on pH or whether or not your plants show Ca deficiency.

 

[FunkBomb]

Gypsum is a great soil amendment. It helps loosen up clay soils and has a lot of calcium.

-Funk

 

[Mikell]

http://pubs.ext.vt.edu/452/452-510/452-510.html

Not a substitute for lime, but commonly used together.

 

[moses wellfleet]

Great link, thanx!!

 

[moses wellfleet]

I’m got some elemental sulfur (fine yellow powder) left over from a sulfur burner which I no longer use. I’m planning to add a little of that to the soil mix and see how it goes.

 

[Three Berries]

Gypsum is a very slow release source and is great for clay soils, or compost. Limestone, which varies in composition but is usually <50% Ca and > 50% Mg carbonates. My local stuff is 90/10 Ca/Mg and makes my well water 450-550 ppm and 7.4 pH.

Limestone with carbonates is a buffer and will try and maintain it's pH point until exhausted by reaction with acids releasing CO2 gas and the elemental Ca or Mg. Or sodium if you are unfortunate to use it.

Too much limestone and the pH stays high, too little and it will stay low. Just did a grow with Ocean Forest that sailed though great pH wise and I used a cup of Nutralime DG commercial limestone to 3 gal of soil.

So limestone is great if low pH is an issue and short term needs are there. For immediate relief of deficiencies you can use Calcium Acetate or Calcium Chloride directly to the soil or foliar at ~1000 ppm concentrations. They both completely dissolve in water and make active ionic solutions. Same for Magnesium Chloride or acetate or Potassium.

Edit: When they talk about and sell in the stores as Lime around me they are talking about slaked lime or Calcium Hydroxide. Rather potent stuff. high pH wise.

Calcium hydroxide
Inorganic compound of formula Ca(OH)2
Calcium hydroxide (traditionally called slaked lime) is an inorganic compound with the chemical formula Ca(OH)2. It is a colorless crystal or white powder and is produced when quicklime (calcium oxide) is mixed or slaked with water. It has many names including hydrated lime, caustic lime, builders' lime, slaked lime, cal, and pickling lime. Calcium hydroxide is used in many applications, including food preparation, where it has been identified as E number E526. Limewater, also called milk of lime, is the common name for a saturated solution of calcium hydroxide.Wikipedia

 

[Bio boy]

http://www.spectrumanalytic.com/support/library/rf/Gypsum.htm



dank.Frank

My gypsum has double the sulphur stated here ? Why?

 

[Three Berries]

I’m got some elemental sulfur (fine yellow powder) left over from a sulfur burner which I no longer use. I’m planning to add a little of that to the soil mix and see how it goes.

That should lower the pH in the soil. I've been looking for a soil acidifier for my evergreens.

 

[Sasult]

Nice thread. I have done some reading on gypsum before and still thinking to add to my mix as I found out too much dolomite lime will raise ph over 7.

I use the PH spike from dolomite and diatomaceous earth as an excuse to add peat,or sulfur. Soil acidifier is just sulfur derived from gypsum. I do use gypsum also, but about half as much as dolomite.

I'm still fine tuning so thanks for the reading material.