What would be good reading material for someone trying to understand the basics of NPK while going further than just what nitrogen phosphates and potassium is.

Mineral Nutrition of Higher Plants by P  Marshner. Be sure to learn how secondary & micros work work with NPK to integrate the von Liebig principal that all nutrients are equally important

The CCA or Certified Crop Adviser(red book) study guide does a pretty good job and includes some quiz material. There is a book on Amazon called Soil Science Simplified. There is a multitude of websites also.

Look for books by Les Henry

https://images.app.goo.gl/rTjY9bPuAPky9c7Y9

These are fundamental reading to understand soils.

I think Soil Fertility and Fertilizers (Tisdale, Beaton, Nelson and Havlin) is good and Mineral Nutrition of Higher Plants (Marschner)

Montana State nutrient management modules are well done! https://land resources.montana.edu

Response from Jason Hanson in Fertilizer, Soil, Nutrients | AGvisorPRO

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