>>142895samefag again
>>142917It depends on what root vegetables you are planning to grow. Next to nutrients, another (probably even more) important factor to consider is diseases. A depleted soil can be replenished in between growing seasons. A disease that gets a foothold in your soil will take 4 years or more of not growing anything that's susceptible to it to get rid of it. Planning your rotation may initially seem more complex than it is, but keep at it, you'll see the logic behind it at some point and it pays of in the long run.
I always start by googling to which 'plant family' a crop I wish to grow belongs (Like peas belong to the Fabaceae family). Most diseases or pests are somewhat confined to a specific family or a select group of families. ( Like blight in the Solanaceae family (tomatoes, potatoes, ..)). I always make sure it takes multiple years before plants susceptible too a specific common disease get planted in the same soil again.
It's not always possible to perfectly marry 'rotation for disease control' with 'rotation for avoiding soil depletion'. I manage by working in some extra manure and compost when needed to compensate.
Pic unrelated; today's batch. The delight of having a garden..