Gypsum

OldMedUser

Well-Known Member
Sure. As long as you don't go overboard with it.

Like dolomitic lime it breaks down slowly in soil and you have to watch what other things you may add that you don't give too much of one substance throwing others out of balance.

A good source of sulfur for your plants especially when they are flowering and helps contribute to resin production. Epsom salts is another good source of S and Mg.

:peace:
 

Wetdog

Well-Known Member
Just as OldMedUser suggested.

Just don't make the mistake of trying to substitute it for lime or, to buffer your soil, it won't. For soil buffering, the calcium has to be in a carbonate form (such as lime), gypsum is in a sulfate form. Great as a Ca and Su source, but lacking buffering ability.

Wet
 

Tim1987

Well-Known Member
Its a fantastic amendment! I love it.
You dont use gypsum for the same purpose as lime. It doesn't alter your ph.
Whats so good about gypsum, is it buffers the soil, so the ph doesn't swing easily at all.

Say you have a soil thats ph 6.5. Well why use lime? The ph is fine.
Gypsum still provides calcium, as well as the benefits of sulphur. But buffers the soil to stay at 6.5. Its fabulous stuff. Really!
Gypsum also breaks up sodic, clay soil.
 

NaturalFarmer

Well-Known Member
I have done a few experiments with gypsum and have found that too much in my mix gives a very nasty aftertaste to the smoke.
I ran four mixes in 2 cup increments and only really found awful taste beyond 6 cups of gypsum to 35-45 gallons of soil (45 gallon bags mostly full). 8 cups was almost unsmokeable (I smoked all of it).

2 cups per grow on a large plant should be enough but 4 cups was the sweet spot for my mix.
 

NaturalFarmer

Well-Known Member
There is another thread that I started about gypsum a few years ago or so with a lot of information on gypsum(much more than most would want). I almost hate to link it because it was overrun by bickering and was probably not my best hour but it has a lot of links so here it is.
https://www.rollitup.org/t/gypsum-anyone.930193/

But this video sums it all up
 
Last edited:

NaturalFarmer

Well-Known Member
Another source calcium carbonate input is hardwood ash which also gives up a good amount of K as well. I use ash from my fireplace along with crab shell as my carbonates in conjunction with gypsum.
 

NaturalFarmer

Well-Known Member
Last edited:
Top