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Fertilizer Question #928758

Asked April 17, 2026, 6:06 PM EDT

Hello - Based on my soil sample results from the University of Minnesota for my vegetable garden. The report indicates that my phosphorus (P) levels are already high and do not require any additional applications. Given these results, what fertilizer would you recommend to applying and incorporating into the soil at planting in the spring ? While I typically use high-nitrogen fertilizer as a side dressing for sweet corn, I am aware that high nitrogen is generally not ideal for root crops. Most "Garden Fertilizers" are balanced blends like 10-10-10 or 17-17-17, whereas phosphorus-free options are often limited to lawn fertilizers. I would appreciate your guidance on a suitable fertilizer choice that accounts for my high phosphorus levels while remaining appropriate for a variety of garden vegetables.

Anoka County Minnesota

Expert Response

Minnesota soil tends to be high in phosphorus naturally.  Here is an excerpt from one of our articles:  

What you can do

  • Take a soil test from your lawn or
    garden every few years. If your soil phosphorus levels are above 25
    (Bray test) or 18 (Olsen test), do not use a phosphorus-containing
    fertilizer for a few years, until your levels drop to a point where your
    soil test recommends more phosphorus. Keep in mind that compost often
    contains phosphorus, especially if it contains manure.
  • If you
    have enough phosphorus in your garden but still need nitrogen or
    potassium, consider options like feather meal or blood meal (nitrogen),
    and potassium sulfate or langbeinite (potassium). These products will
    not contribute excess phosphorus.
  • If you add a thick layer of
    compost to your garden each year, consider your compost as a source of
    nutrients. Usually, compost has low nutrient concentrations, but when
    used in large volumes, or when using manure-based composts, the nutrient
    contributions can add up.
  • Consider using cover crops in your
    garden. They can provide nitrogen and they build your soil health
    without adding extra phosphorus to your soil.
I do not have access to your report but would suggest using blood meal.  It is very concentrated so do not over apply.  You do not need to apply to the entire garden but only where your seeds/plants are.  You may be able to find bags designed for vegetables (i.e. Tomato Tone for tomatoes, etc.) Too much fertilizer is more harmful than not enough. Some plants, like peas and beans, actually add nitrogen to the soil. Look at your soil test report again and note that under each reading it will suggest the amount needed for each individual nutrient.  It may suggest a bare minimum.  In that case, don't worry about adding any to your soil this year.  It may be that your gardening costs will be lower this year.

Barbara, Anoka County MG, TCA Replied April 18, 2026, 4:02 PM EDT

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