Time of ridging

Often only a shallow ridge is made at planting.
A larger - final ridge - is either made soon after planting, at the start of crop emergence or at the crop stage where plants reach 15-20 cm height.
Early ridging is done when the temperature after planting is expected to be relatively high (>12-15 oC) and it is expected to be dry.
If the final ridge is made at planting herbicides with a residual effect are used.

Ridging procedures
Early final ridging
Ridging at planting is applied when:
Delayed final ridging

With cool soil conditions at planting time and/or when mechanical weed control is applied only a shallow ridge is made at planting. When plants are near emergence a second ridging takes place. With this second ridging the size of the ridge increases and weed is controlled. A third ridging is applied when the plants are 15-20 cm high. With this operation the ridge is re-shaped and weed is controlled. The ridge has now reached a size where the tubers are well protected by a layer of soil.
Ridging before emergence----Ridging at emergence----Re-ridging