My brother-in-law planted some spuds in two tubs, as an experiment, he filled one to the top, the other he earthed up a couple of times. I found three old ones in the bottom of my tater bag with 2 – 3″ sprouts so I put them in a tub and earthed up a couple of times, we shall see what appears! Tops are looking good, the taters came from Collins at Bromham, which is a sort of mini garden of England between Devizes and Chippenham, here in Wiltshire.