I know that different vegetables require different levels of NPK. My question: Is there a general guide for these amounts? Thanks
Optimum Soil Nutrients for a Vegetable Garden in Sandy Soil
Certified GKH Gardening Expert
This article on interpreting soil tests gives you the general ranges that are considered healthy for all nutrients in the soil:
While vegetables do need different levels, you can kind of think of your soil as a buffet for your plants. They will take what they need and you just need to make sure you have enough of any and all nutrients to keep them happy.