Potash Policy

[Clive]

What's yours ?

timing ? rates ? type ?

is SOP worth the premium over MOP ?

 

[Feldspar]

Well I've just ordered SOP rather than MOP based upon what I've read. Only on a trial scale so the economics are different. It depends on how much S you think you need among other things.

http://link.springer.com/article/10.100 ... 01?LI=true

Question to ask is if kills these bacteria, what else does it wipe out? KCL is the main component in the lethal injection - not very nice stuff from the limited amount I've read. Worth a bit of a research.

 

[chewdles]

Well I've just ordered SOP rather than MOP based upon what I've read. Only on a trial scale so the economics are different. It depends on how much S you think you need among other things.

http://link.springer.com/article/10.100 ... 01?LI=true

Question to ask is if kills these bacteria, what else does it wipe out? KCL is the main component in the lethal injection - not very nice stuff from the limited amount I've read. Worth a bit of a research.

Hello everyone.
If your looking for a good explaination about MOP and what its chlorine part does to the soil,plant roots and soil bugs go to page 43 of this book the "Organic Pastoral Resource Guide"
http://www.organicpastoral.co.nz/site/o ... LowRes.pdf

 

[Clive]

Well I've just ordered SOP rather than MOP based upon what I've read. Only on a trial scale so the economics are different. It depends on how much S you think you need among other things.

http://link.springer.com/article/10.100 ... 01?LI=true

Question to ask is if kills these bacteria, what else does it wipe out? KCL is the main component in the lethal injection - not very nice stuff from the limited amount I've read. Worth a bit of a research.

Hello everyone.
If your looking for a good explaination about MOP and what its chlorine part does to the soil,plant roots and soil bugs go to page 43 of this book the "Organic Pastoral Resource Guide"
http://www.organicpastoral.co.nz/site/o ... LowRes.pdf

Thanks for that - interesting stuff, SOP it is then !

 

[Andy Howard]

We hardly use any. If we do it is SOP. The question you should also ask is "do you need kgs of Chloride?" If not then use SOP because sulphur is something you probably do need.

 

[Richard III]

I agree with Andy, put on what you need. Sulphate and chloride are both essential elements for crop growth, but sulphate far more likely to be limiting.

I don't have full access to of the springer article, but they don't seem to have compared potassium chloride with other forms of potassium, and they seem to me to have used huge application rates. If I have got my sums right, no wonder they suppressed nitrification.

The organic article compares potassium chloride to chlorine in swimming pools, swimming pool chemicals release free chlorine whereas potash only contains the chloride salt. It is very misleading to suggest the two have the same sterilizing effect.

My understanding is pretty much all chemical fertilizers are harmful to soil life, that's one reason why I buy in quite a lot of compost and then use low rates of sulphate of potash as and when required.

 

[SilliamWhale]

why not high K fibrophos?

+1 on Chloride is not Chlorine. Its naughty of that article to imply that.

 

[TWF]

We don't need to put large quantity on but need to do a large area . Haven't used much the last few years as we have huge reserves but high Ca . My thinking is there must be a lot more worse things on with all this stacking of Black Grass residuals.

 

[Feldspar]

We don't need to put large quantity on but need to do a large area . Haven't used much the last few years as we have huge reserves but high Ca . My thinking is there must be a lot more worse things on with all this stacking of Black Grass residuals.

Just remember what Kinsey said about the ability to build K levels with artificial fertilisers if your pH is high (which it may well be if you have high Ca). If the pH is above 7.5 then K fert should only be used in sufficient amounts to feed the crop. Organic manure will build K though above ph of 7.5.

 

[JNG]

We don't need to put large quantity on but need to do a large area . Haven't used much the last few years as we have huge reserves but high Ca . My thinking is there must be a lot more worse things on with all this stacking of Black Grass residuals.

Just remember what Kinsey said about the ability to build K levels with artificial fertilisers if your pH is high (which it may well be if you have high Ca). If the pH is above 7.5 then K fert should only be used in sufficient amounts to feed the crop. Organic manure will build K though above ph of 7.5.

I am re-reading hands on Agronomy having come home from last weeks talk and last night read the section on K (page 181), it was actually even if the pH is over 6.5 (water pH), only chemical K for feeding the plant above this level, the soils levels cannot be increased unless through organic manure like Feldspar says. We are also on high Ca soils here with pH's of 7-7.5 and have traditionally spread a % of K in the Autumn to 'build reserves'. Spring only application from now on I think??? Saying that the soil levels of K are fairly good so maybe it did work :?: