I dig my potato's up when I see the plant dying back or wilting. I also pinch out any flowering or seed (Green tomato).I only water when its quite dry or its warm weather as they don't like cold wet conditions.I'm using Duke of York first early this year which I have chitted. Although last year my cupboard sprouting potato were planted and had very good clean crop, these were well spaced and abt 12" deep for good size potato. If you plant shallow and close you are suppose to get a heavier crop.Plant further apart for larger potato's, I'm trying both methods this year. good luck all, enjoy.
