# I need to put down K this fall... Granular or liquid?



## Glen_Cove_5511 (Jun 13, 2020)

According to my Waypoint soil test results, I need to put down 3 lbs./M potash this fall. Looking for suggestions on which product to use and if I should do granular or liquid. Thanks


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## Virginiagal (Apr 24, 2017)

See what you can find locally. Read the soil remediation guidelines:
https://thelawnforum.com/viewtopic.php?t=15165

This discussion will also be of interest:
https://thelawnforum.com/viewtopic.php?t=17196&start=10


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## Glen_Cove_5511 (Jun 13, 2020)

Thanks @Virginiagal, I'll check those links out.


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## RBall (Mar 16, 2021)

I've read through both and don't see there is really a difference. Is that safe to say both are fine and it's a price/personal preference?

I spoke wth AgSource (Agronomist) regarding Potash and they told me to stick with 0-0-60 when you can to avoid the Sulfate Sulfer...

From the LawnForm Soil Guidelines:



> Potassium
> For potassium there are two main options:
> 
> Sulfate of Potash (SOP) 0-0-50. Apply at no more than 2lb/ksqft/month. This will also provide some sulfate sulfur the plant needs too. It can be hard to find. Go to the hometown folders in the forum to ask someone local to your state for sources.
> ...


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## Virginiagal (Apr 24, 2017)

SOP has a lower salt index than MOP. Some reading material on the differences:
https://nutrien-ekonomics.com/news/potassium-fertilizers-muriate-of-potash-or-sulfate-of-potash/


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## corneliani (Apr 2, 2019)

Glen_Cove_5511 said:


> According to my Waypoint soil test results, I need to put down 3 lbs./M potash this fall. Looking for suggestions on which product to use and if I should do granular or liquid. Thanks


Am I reading this correct, you're needing to apply 3#Potash - this fall? Or is it over the growing season(?). If the latter I would think that spreading it out to include some apps in late spring/early summer would benefit the plant ahead of summer stress/dormancy. That's when the heavy-potash ferts are thrown down on TTTF. 
Warm season turf recommends 1#Potash as the last app of the year, ahead of winter dormancy.

Edit: to your question, granular will always apply more pounds on the ground than liquid will. Liquids are great foliar apps though.


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## Glen_Cove_5511 (Jun 13, 2020)

@corneliani Waypoint recommended a total of 3 lbs./M. Makes sense to spread it out and after taking a second look at my soil report, that's what I'll do since I have sandy soil.


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## Bkeller500 (Jul 2, 2018)

FWIW, I need to do the same. My plan is to monitor the local Big Box stores and try to catch some sales on Lawn Starter Fertilizers and throw it down. And possibly again in the Spring. Menards seems to have a couple of good options right now.


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## ScottW (Sep 16, 2019)

Glen_Cove_5511 said:


> @corneliani Waypoint recommended a total of 3 lbs./M. Makes sense to spread it out and after taking a second look at my soil report, that's what I'll do since I have sandy soil.


You can apply 1 lb per month.
Even after applying your total recommended 3 lbs, you're probably going to be low again next spring. That's how it has been for me the past couple of years. There is a few ppm improvement year to year, but because K slowly leaches from the soil a lot of what you put down will be lost over the winter. And that's in my clay loam, in sandy soil fuhgeddaboudit.
Plants can use about half as much K as N. This year I used some Lesco 18-0-18 for my early N, and later applied another 1 lb of K from MOP. I have since replenished my stock of SOP and I jumped on a couple bags of Lesco 30-0-10 in that sale at Lowe's. Plan is to generally be throwing down some K along with the N.


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## Ridgerunner (May 16, 2017)

> I spoke wth AgSource (Agronomist) regarding Potash and they told me to stick with 0-0-60 when you can to avoid the Sulfate Sulfer...


Did AgSource give an explanation as to why you need to avoid Sulfate?


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## 7824 (Oct 23, 2019)

Granular 0-0-50. 1lb of K per month. SiteOne carries it around here.


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## RBall (Mar 16, 2021)

Sorry for the dumb question, but isn't 1LB Granular or 1LB Soluble the same thing? Does it matter if it's granular vs sprayed? I'm in the same boat - just figured out my K is low as well.


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## Virginiagal (Apr 24, 2017)

Here is an example of a liquid potassium. 
https://cdn.shopify.com/s/files/1/0728/3039/files/GROWTHPRODUCTSLIQUIDPOTASSIUMSOLUTIONLABEL.pdf?v=1583627193

Note that 1/8 - 1/4 lb of potassium per 1000 sq ft can be applied in one application. Applications can be repeated every 7-21 days. In contrast, for granular SOP (0-0-50), 1 lb of potassium (2 lb of SOP per 1000 sq ft) can be applied in an single monthly application. 
Note the price: 
https://wallacewow.com/products/growth-products-0-0-25-liquid-potassium
For $139 you get 2.5 gallons of the liquid product which has 2.8 lb of potassium. Home Depot has a 40 lb box of granular SOP for $44 which has 20 lb of potassium.


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