Potato Sperry

This year I grew Arran Pilot first earlies.  I had some in the ground and some in recycling boxes.  They were grown in similar positions in the garden.  The boxes were beside a raised bed.  I harvested at the same time.  The yields were enormously different.  For the same area I reckon I had about three times the yield.  What is more from the boxes the spuds were very similar sizes and smaller than in the ground.  Of course it was easier to make sure I got all the spuds out of the box.

Is this other peoples experience?  Is this the same with second earlies and salads as well.  I am probably just going to do boxes next year

We grew a few varieties (7 - long story) last year in containers, well large bags actually. The yields were all small, as in small numbers of spuds. This year going back to growing them in the ground albeit a late decision and therefore an area of ground which should have been prepped better, we're getting much bigger yields.