Don't go Jazz! Almost everyone here is friendly and wants to help and be helped
. And I understood your question perfectly. I'm no expert but I would count everything you've grown in the last 12 months in a particular bed as being something you would want to put somewhere else in the next 12 months. So in your example, I'd grow both spuds and kale etc elsewhere next year.
re beans: I rotate mine because a) I assumed you had to and b) their roots fix nitrogen in the soil and it seems to me this might be a useful thing to do in a different place each year. However my allotment neighbour has a permanent bean-supporting structure set up, never rotates and his beans are always very healthy. So...make of that what you will.
Happy growing!
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