[photochemsyn]

Apparently soybeans are often grown in a double-cropping rotation, in which maize is planted first (along with N and P fertilization), and then no additional fertilizer is applied to the following soybean crop.

This seems to be a comprehensive discussion (for South Dakota farmers anyway, pdf):

https://extension.sdstate.edu/sites/default/files/2020-03/S-...

[cmroanirgo]

Making use of nitrogen fixing plants alleviates the need of fertilization. An easy one: clover. Bees also love clover. However you can explore other systems of cover cropping (I recall Diakon radishes draw up nitrogen from down low, up to the surface) which you terminate before seeding your main crop.