Before modern seeders were common, farmers used to broadcast 1/2 oats and 1/2 potash. No fertilizer bin needed.
Oats use a ton of potassium.
look at this pdf starting around page 70.
The year I don't buy a bag of oats is the year I stopped hunting....... Mix some into my rye plantings. They frost die, then make room for rye in the spring.