The manure did you a world of good, wish I could get some from the neighbors, but I'm always a 1/2 mile farther to drive than someone else.... The micro nutrients in it adds more than just regulare fertilizer.
Granular fertilizer, and manure too, often is kinda applied this year to be there for the future. It takes a while for it to break down - either way, manure or granular - into stuff the roots can take up.
So you probably only used 1/3 of the fert you put down on this year's crop, and this year's crop likely was using a lot of what was left from the renter.
Good of you to keep the soil fed and balanced, lot of hobby folks take on a little plot and say, well it grows so good, don't need to waste money on that fertilizer....
It shows up in a few years, and then takes a lot to bring things back up to where they should be.
Sounds like you are doing a real nice job.