The group we call root vegetables covers a wide range of types, and some of these root veggies will need a slightly different way of preparing the soil.
Potatoes make up the largest part of the root group, the rest being carrots, parsnips, beetroot, celeriac and two vegetables that you may not have tried, scorzonera and salsify.
The trouble with soil preparation for the root veg is that we have to split the root group into two separate groups, the root group and the tap root group.
The root group includes potato, beetroot and celeriac, and to prepare for this part of the bed it's best to heavily dig in a minimum of one wheelbarrow full of well-rotted manure per square meter.
You can cover the bed with manure in Autumn and rotavate it in in the spring, this really loosens up the soil, making it free draining.
Alternatively you could double dig this area, by digging a trench at
one end of the bed, filling it with manure, digging a trench next to it
and using the contents of that trench to backfill the first, and then
filling the second trench with manure, repeating until you reach the end
of the bed where the contents of the first trench can be used to
backfill the last.
This manure rich soil is an ideal growing medium for the general root crops, but is far too rich for tap root type plants.
Carrots, parsnips, scorzonera and salsify send one long root down into the soil, and if the soil is to rich, the roots will have tendency to split.
We would not manure this area of the root bed, instead we would add either a general fertilizer such as fish, blood and bone or a leaf mould, but first we would riddle the stones out of bed to provide a stone free environment.
If your plot is very stony, either plant stubby carrots and parsnips, or have a look at our how to grow carrots page for some good tips on growing on stony ground.
Most of the root group tend to be sown in a particular way and they have a particular selection of root vegetable insects and diseases that attack them, have a look at the growing root vegetables page for tips on sowing, care, pest and diseases.