low potassium soil

Question: Our soil test came back showing low potassium in our lawn soil (front yard only)  All other test results are ok.  So adding potash seems the likely remedy. But big box stores don't sell potash.  I did see it on Amazon.  My takeaway is adding potash is not common.  Is it effective to add potash  or are there other practices to try. Thank you

responder: An Ask Extension Expert Replied August 01, 2024, 12:11 PM EDT
response: Thanks for your question. In order for me to provide you with accurate information, I would like to see a copy of the soil report.  Could you please provide us with a picture of it? Many thanks.

responder: The Question Asker Replied August 01, 2024, 2:35 PM EDT
response: Here is soil test.    Nancy   From: ask=<personal data hidden> <ask=<personal data hidden>> On Behalf Of Ask ExtensionSent: Thursday, August 1, 2024 11:12 AMTo: Nancy Melink <<personal data hidden>>Subject: Re: low potassium soil (#0149643)

responder: An Ask Extension Expert Replied August 03, 2024, 8:20 PM EDT
response: Thanks much for the report.  Will look it over and get back to you with a detailed analysis.  For the interim, there really is nothing to be concerned about regarding the potassium levels.  Details to follow. Thanks again for the report and thanks for consulting with us.

responder: An Ask Extension Expert Replied August 04, 2024, 11:26 PM EDT
response: Thanks again for the soil test. Upon looking over what you sent, it is not completely clear to me what you are asking. Potassium level is one thing, but is there something else? On the soil report there is some writing. Perhaps it’s yours? Directions for your front yard about letting it grow longer and sharpening the mower blades are spot on. Whatever you think may be wrong with your yard, aeration is not necessary. You have a very healthy organic matter (OM) content of 11.4%. To achieve this high level, my guess is that you leave your grass cuttings on the yard and/or mulch your fall leaves. Whatever. Both are very sound practices. Continue them. With this high OM level, aeration is not necessary. I am slightly puzzled by the writing of adding gypsum. Chemically it is calcium sulfate. It has nothing to do with potassium. It is often used to break up clay-compacted soils and to provide calcium to your yard. Because of the high level of organic material (11.4%) in your yard, I don’t see any need for gypsum. I would suggest that you disregard the comments about gypsum. See: https://www.masterclass.com/articles/gypsum-applications-explained https://www.thespruce.com/how-to-use-gypsum-in-gardening-5079656 As to your potassium level, the soil report suggested 4 pounds potassium per 1,000 square feet. Potassium is usually added as potash. If you look in gardening centers, you will typically find potash labeled “Muriate of Potash”, 0-0-60. If you closely look at the product label, you should see that it is potassium carbonate (KCO3). Consistent with the product label, one pound of the product contains 0.6 pounds (60%) of potassium. It comes as a powder. See: https://www.cropnutrition.com/resource-library/what-is-potash/ The recommendation for potassium was 4 pounds per 1,000 square feet. So measure your yard and determine its total square footage. Suppose it turns out to be 1,250 square feet. If so, you will need to add (4)x(1.250) = 5 pounds of potassium to it. In every pound of muriate of potash there is 0.6 pounds of potassium. So for a yard that is 1,250 square feet, you would apply slightly over 8 pounds of potash. I got this number by dividing 5 by 0.6 But in a broader content, the soil in your yard is quite acceptable even with a low potassium level. I really don’t see any major issue. So my question to you is why would you want to do anything? What do you currently find troublesome about your turf?” Thanks for your question. If you feel that there is some follow-up that needs to be addressed, we will attempt to assist you. If you elect to do nothing about the potassium levels, no harm would be incurred. Good luck

responder: The Question Asker Replied August 05, 2024, 2:36 PM EDT
response: Thank you for your thoughtful response.    I am sending a couple photos to show area of concern  which is in our front yard, which has very little shade. ( Our back yard grass is much better as it has more shade.)  Low potassium as our only out of range nutrient, as you said doesn’t add up as the only culprit.  We think our watering practices over the last 3 years or so are  part of the problem (especially last years dry spell)  We didn’t water deep enough and too frequent,  is what we are thinking .  We are going to put a rain guage out there when we water to insure 1 inch once a week, unless rain occurs.  We also 2 days ago fertilized according to a lawn experts advice at Martys Farm Service in Elk River.  This included a potash application, a small amount of gypsum for sulpher, and a 2 part application of a 19-19-19 blend.  This is a one time “remedial” fertilization.  Next year we will do 27-0-7 application 3x/year.  Thanks again!   From: ask=<personal data hidden> <ask=<personal data hidden>> On Behalf Of Ask ExtensionSent: Sunday, August 4, 2024 10:27 PMTo: Nancy Melink <<personal data hidden>>Subject: Re: low potassium soil (#0149643)

responder: An Ask Extension Expert Replied August 05, 2024, 3:53 PM EDT
response: Thanks for getting back to us. It seems that you are pretty much on top of things but want some areas (front yard) to be better). At this time of the year, most turf enters a period dormancy and may even turn a bit brown. It is a “resting period”. While I’m sure that the good folks at the Farm Service had only the best intentions, now during the hot part of the summer is not the best time to apply fertilizer. It could lead to burning of your turf. Look at the following turf calendar and schedule which has been developed by the University of Minnesota for best practices. Note the warning about fertilizing a lawn during hot summer months: https://extension.umn.edu/planting-and-growing-guides/lawn-care-calendar https://extension.umn.edu/yard-and-garden-news/hot-weather-fertilizer-tips-your-yard-and-garden I will again raise the question of why you are adding gypsum to your yard? Rarely is sulfur deficiency a cause of turf problems. If given in high enough amounts and over a long period, sulfur can lower the pH of the sulfur. However the pH of your soil is within an acceptable range for growing grass. See: https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/using-gypsum-in-garden.htm - :~:text=In short, you can benefit,left for industrial agricultural use. https://s3.wp.wsu.edu/uploads/sites/403/2015/03/gypsum.pdf With respect to watering your yard, the following are what we consider to be “best practices”: https://www.lakevillemn.gov/277/Lawn-Watering-Facts-Tips - :~:text=It's best to water established,nos shorter than two inches. https://extension.umn.edu/how/water-wisely-start-your-own-backyard Finally for the spots in your front yard that may need some improvement, consider doing overseeding for them during the latter part of August to early September. See: https://extension.umn.edu/lawn-care/seeding-and-sodding-home-lawns Thanks again for using our services. Please get back with any additional questions.

responder: The Question Asker Replied August 05, 2024, 4:40 PM EDT
response: Hello again,   Regarding timing of fertilizing a couple days ago…we saw that 70 degree temps were forecast this whole week our so we went ahead because of that.   Part 2 of the 19-19-19 we will put down in mid September.  We will overseed as you suggest also. Thanks, Nancy   From: ask=<personal data hidden> <ask=<personal data hidden>> On Behalf Of Ask ExtensionSent: Monday, August 5, 2024 2:53 PMTo: Nancy Melink <<personal data hidden>>Subject: Re: low potassium soil (#0149643)

responder: The Question Asker Replied August 05, 2024, 4:46 PM EDT
response: Regarding sulpher, the lawn guy recommended a small amount so excess shouldn’t be a concern.  He said most lawn soil testing he does in this area show a sulpher deficiency.  Our lawn ph at 6.8 is good but a 6.5 would be better.  Figured we couldn’t go wrong with adding the small amount he recommended.  Next year I am going to send in soil to the U for another analysis, and having micronutrients added to the testing.   From: ask=<personal data hidden> <ask=<personal data hidden>> On Behalf Of Ask ExtensionSent: Monday, August 5, 2024 2:53 PMTo: Nancy Melink <<personal data hidden>>Subject: Re: low potassium soil (#0149643)

responder: An Ask Extension Expert Replied August 05, 2024, 4:52 PM EDT
response: Thanks again for your response.  Getting a soil analysis done next spring would be a great idea.  If not before then, I'll look forward to working with you at that time.  Thanks for using our forum.