By the looks of your photo, the only thing you did 'wrong' was to take them out a bit early. The two smallest ones would have caught up with the rest in a couple of weeks!

really? I was told once they finish flowering to dig them up, that was last week. How long do they keep growing for after they have flowered? One other thing which springs to mind should i have planted 2 tubers in one planter?

This is the first time I have had a go at spuds. I bought special bags for spuds, they come with instructions. The dimensions are: 14" dia x 18" high. The instructions said to plant 5 seeds to each bag. So far so good with mine. Have got lots of foliage so am hoping that I'll get a good crop Perhaps you should have planted more seeds in your containers??? (dependant on the size, of course!) Good luck for your next lot.

Womble if you have space it really is much easier to sow your potatoes in the ground. We experimented with using the potatoes bags you can buy in gardening stores last year and the crop was nothing like that which we got from those grown in the ground. The tubers will keep growing for a while after the potato has flowered, also not all potato varieties flower or the flowers can be very small and insignificant. A good rule of thumb is to allow 12 weeks from planting your early potatoes to harvesting. Leaving them longer than this will not cause any problems, as new potatoes do not keep well just lift the amount you need for a meal.

I grew potatoes in bags last year (first time growing potatoes) and was disappointed with the yield. This year I am growing 2nd earlies in the ground and have already started harvesting, I planted chitted varieties just before Easter. I don't wait for flowers ... my plants don't seem to produce flowers, but start rootling around to check for size and I just harvest those that are the right size I require, and only harvest the amount that I plan to eat that night for supper! Depends on variety too .. my 'Winston's' are ready, whilst 'Belle de Fontenay' are still pretty small so I am leaving those in until they reach the size I require.

Koicarp, its sounds like your bags are a little bigger than mine so next year i will try more than one tuber. its just a shame when things dont go to plan you have to wait so long until you can try again.
i shouldnt complain though as my friend gave me the tubers for free and with full instructions. i think all in all i waited 13/14 weeks as they took a little longer to flower. Unfortuately i dont have a big enough garden for my spuds to be grown in the ground but a few weeks ago i built 3 new planters so i think next year i will grow them in there.

Thanks for everyone responses and i have just one last daft question - why do you need to earth up the plant?