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s10sleeper

Soil Ph, nitrogen, phosphorous and potash levels

s10sleeper
11 years ago

I decided to test my soil levels in my lawn I have been trying to establish. In testing the soil I found that my pH level was about 7.0, Nitrogen levels extremely high, Phosphorous very low and Potash medium.

As I recall, phosphorous is necessary for root development and vital for starting a lawn from seed. If this is correct, I wonder if this is the reason my lawn is so patchy. I used to have an issue with bindweed, but have been able to get it maintained by treating it last fall and now whenever I see one starting just paint the leaves with a little roundup. Those areas of grass that do die from that I don't worry so much about, it is the areas that do not grow in at all I am concerned about. The only phosphorous supplement available around here is bone meal, I used to be able to find super phosphorous but it is impossible to find. Is this the cause of my problems growing grass? Also, I have alot of clay in the soil and so have also been trying to work in some compost and peat moss which has made the soil a little loamier.

Comments (7)

  • blazeaglory
    11 years ago

    Just a suggestion...

    To revitalize an old lawn: Use 7 lb alfalfa meal, 4 lb soft phosphate, and 1 lb kelp meal per 100 sq ft. Apply in spring, and water well twice a week for 2 weeks. You should see results in 6 weeks. Over seed if necessary.

  • blazeaglory
    11 years ago

    Considering your Nitrogen levels are high I would cut out the alfalfa meal. Either way its just a suggestion from an organic website I know of.

  • Kimmsr
    11 years ago

    Did you use one of those soil test kits from a garden center that are not very reliable?
    The soil pH is about 7.0 but what is the amount of Calcium and Magnesium in that soil?
    Nitrogen is stated as "extremely high". From what? Did you add Nitrogen before having this test done? Very few soil testing labs test for N because it is so volatile and dependant on how active the soil bacteria are which depends on soil temperature.
    Because of the high levels of Phosphorus being found in our lakes and streams, from over fertilization, most states now ban P in fertilizers. You could get some if you had a soil test from Kansas State University that showed a need for P in your soil.
    Adding organic matter to your soil will not make it more "loamy" unless you have a soil composed of about 45 percent sand, 25 percent silt, 25 percent clay, and 5 percent organic matter, although the organic matter will make any soil better.
    I would go to my local KState Cooperative Extension Service office and inquire about having a good, reliable soil test done before proceeding further.

    Here is a link that might be useful: KState CES

  • General
    11 years ago

    Phosphorus is a nutrient required by all organisms for the basic processes of life. Phosphorus is a natural element found in rocks, soils and organic material. Many soils are naturally low in phosporous. In addition, phosphorus clings tightly to soil particles, so its concentration in clean waters is generally very low. As a result, it becomes the "limiting" nutrient with respect to plant and algie growth in streams and lakes. Bacteria feed on dead plants and algie, and consume the available oxygen in the water. Addition of phosporous fertilizer to soil containing low levels of this nutrient may be necessary for good plant growth.

  • toxcrusadr
    11 years ago

    I doubt you would have any trouble getting high P fertilizer in the Great Plains breadbasket. I was not aware that some states have banned high P fertlizer due to water quality issues, but it's certainly not happening here in MO. I've used quite a bit of 12-12-12 and that would work for you. Just not right now if your N is very high. Fall or spring.

    I'm sure Blaze's recipe will work wonders, but you may not be able to get some of those ingredients. We don't have a lot of kelp here in the Midwest. :-]

  • s10sleeper
    Original Author
    11 years ago

    It is interesting you posted the link to the K-state website, kimmsr, their ag research center is straight south of me a half mile. I figure the nitrogen is high as I have alot of red nightcrawlers in the soil, literally, I can dig up about a cubic foot and have a dozen of them. The pH tester I use is a meter that we used at our farm when we were Jacques seed dealers. The tests for the levels of the others were a Burpee test kit.

    I do live in a floodplain, right next the the main drainage river and have alot of drypan problems with my soil. I decided to add some Scott's turf starter as it was the highest in phosphorous i could find, along with mixing in some turf soil as it was extremely loamy and in some areas mixed in my compost as it broke down extremely fast and was already ready, which was mostly horse manure, equal parts green lawn clippings and thatch from a friends yard with no weeds at all along with tea bags, coffee grounds and eggshells. I threw in a large amount of earthworms in it too and continuously stirred it.

    Once I have the funds I will get an accurate tester. I did find phosphorous at the greenhouse here though also.

  • mackel_in_dfw
    11 years ago

    I was just thinkng about a Luau and I stumbled upon some notes from the University of Hawaii-

    "Amount of clay: As the amount of clay increases in the soil, the P-sorption capacity increases as well. This is because clay particles have a tremendous amount of surface area for which phosphate sorption can take place."

    ...Hawaii, and other tropical soils have P as the limiting reagent, the soils are very sandy... but organic matter in sand or clay does this-

    "Organic matter increases P availability in four ways.

    â¦First, organic matter forms complexes with organic phosphate which increases phosphate uptake by plants.
    â¦Second, organic anions can also displace sorbed phosphate.
    â¦Third, humus coats aluminum and iron oxides, which reduces P sorption.
    â¦Finally, organic matter is also a source of phosphorus through mineralization reactions."

    Then, I went back and looked at some notes from the University of Kansas-

    "A report in 1994 by the Kansas Department of Health and Environment indicated
    that 24 percent of stream miles and 89
    percent of lakes in Kansas were impaired
    by excessive levels of nutrients.
    Phosphorus is the nutrient that is most
    often responsible for the impairment of
    surface water."

    Then, I reread this post from TC-

    "I was not aware that some states have banned high P fertlizer due to water quality issues, but it's certainly not happening here in MO. I've used quite a bit of 12-12-12 and that would work for you."

    Then, I thought back to my days as a youth, walking along the River on the border of Kansas and Missouri, with boyhood dreams of hitchin' a ride on a raft down the mighty Mississippi and winding up in New Orleans, like Huck did. And seein' if I might run into Tox, somewhere on Bourbon Street.

    Mackel