Posted: 08/06/2013 at 22:25
I find the norms a heaped colander full. sometimes the colander is over flowing, when harvested to full term, from 5 spuds planted in spud bags. Your tiddly spuds given a few more weeks would have grown a lot more.
Spuds aren't ready until the foliage starts to die back, usually this is after they flower but some varieties I've grown haven't flowered.
If impatient, you can dip your hand in the bag and have a feel about to pick out some big spuds but I wouldn't advise it until the foliage is dieing back as you could damage the under grounds roots running to the spuds.
When the spuds are ready you can leave them in the bag and just pick the amount you need.