Question Re: Soil Test Results - Ask Extension
We received our soil test results last fall 2016. The results showed our Phospherous P was very high (100+), Potassium K (was also high 281), and our...
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Question Re: Soil Test Results #387630
Asked March 06, 2017, 12:21 PM EST
We received our soil test results last fall 2016. The results showed our Phospherous P was very high (100+), Potassium K (was also high 281), and our soil PH was about 6.7. Our garden performed well the first year (2015) after we added compost provided thru the city. Last year (2016) we added a small amount of oak leaf compost and had disease and insect issues. The garden performed very poorly...which is why we had the soil test done. Based on the test results, how can we get our garden soil back to healthy growing condition for the upcoming growing season?
We grow mostly tomatoes, peppers, beans, eggplant, onions, potatoes
Sherburne County Minnesota
Expert Response
University of Minnesota soil test results include information about what, if any, amendments are needed to improve soil conditions. These are based on measured levels of phosphorus, potassium, organic matter and pH. Nitrogen levels in soil samples are not measured because they leach readily but an amount of nitrogen that should be added for your purpose (vegetable garden) is indicated. The optimum level of organic matter is about 5%. The test results show that P, K and pH were acceptable for your purpose, so it's likely that nothing was recommended to improve these.
If so, what you have told us suggests that factors other than the quality of your garden soil may account for last year's disappointing results. Even so, adding organic matter, annually as needed to reach or maintain a 5% level will be beneficial.
Insect and disease damage to vegetable gardens varies from year to year. Insofar as these may account for poor crops, it's important to identify the particular pests and disease that are present and take measures to control them before major damage occurs. Information at the following websites will be useful in that regard:
https://extension.entm.purdue.edu/publications/E-21.pdf
https://content.ces.ncsu.edu/managing-diseases-in-the-home-vegetable-garden
If so, what you have told us suggests that factors other than the quality of your garden soil may account for last year's disappointing results. Even so, adding organic matter, annually as needed to reach or maintain a 5% level will be beneficial.
Insect and disease damage to vegetable gardens varies from year to year. Insofar as these may account for poor crops, it's important to identify the particular pests and disease that are present and take measures to control them before major damage occurs. Information at the following websites will be useful in that regard:
https://extension.entm.purdue.edu/publications/E-21.pdf
https://content.ces.ncsu.edu/managing-diseases-in-the-home-vegetable-garden
Activity here (Ask an Expert) suggests that you might have submitted this question again in another form. If so, some of the information in the following bulletin is relevant to your continuing concern about the high P and K levels shown in the soil tests results.
http://ccetompkins.org/resources/getting-the-most-out-of-your-vegetable-garden-soil-test-report
In summary, to reduce P and K in your soil, do not apply fertilizers that contain these elements. Also, limit the use of compost and manures high in phosphorus.
Annual cropping (vegetable harvests) will reduce P and K levels in the long run.
University of Missouri authorities address the topic this way:
"If the report shows you have too much of an element, leave it out of fertilizer applications. Plowing just a little deeper for a year or two and sowing green manure crops also will help reduce the effects of those elements present at levels that are too high."
Go here if you want to contact staff at the University of Minnesota Soil Testing Laboratory
Soil Testing Laboratory
Room 135 Crops Research Building
1902 Dudley Ave.
St. Paul, MN 55108-6089
Phone:<personal data hidden>
Fax:<personal data hidden>
Email: <personal data hidden>
http://ccetompkins.org/resources/getting-the-most-out-of-your-vegetable-garden-soil-test-report
In summary, to reduce P and K in your soil, do not apply fertilizers that contain these elements. Also, limit the use of compost and manures high in phosphorus.
Annual cropping (vegetable harvests) will reduce P and K levels in the long run.
University of Missouri authorities address the topic this way:
"If the report shows you have too much of an element, leave it out of fertilizer applications. Plowing just a little deeper for a year or two and sowing green manure crops also will help reduce the effects of those elements present at levels that are too high."
Go here if you want to contact staff at the University of Minnesota Soil Testing Laboratory
Soil Testing Laboratory
Room 135 Crops Research Building
1902 Dudley Ave.
St. Paul, MN 55108-6089
Phone:<personal data hidden>
Fax:<personal data hidden>
Email: <personal data hidden>
