How do you tell when potatoes are ready to harvest?

[Kos]

Somebody told me it's just after their blossom starts dying off?

[Kos]

What an apt name you have Noknowledge

[Kanewood]

Quote: With earlies wait until the flowers are fully open. Carefully remove soil from a small part of the ridge and examine the tubers. They are ready for harvesting as new potatoes when they are the size of hens' eggs. Unquote.

[Clanad]

The green tops can even die back... the longer you leave them in the ground (up to a hard freeze) the larger they will become. We've harvested excellent spuds here in the western U.S. as late as November 1...

[logic]

I used to start lifting mine as soon as the tops started to die back, and just dug them as I needed them, but remember they are a sure target for those wierd underground slugs, the longer you leave them.

[YvonneM]

Dont agree with waiting til the tops have died back the beauty of new potatoes is to catch them before they get too big We harvesting ours and the tops are still really green even then some of the spuds are big

[cumbrianlad]

Broadly speaking 8 weeks after you put them in

[shylock73]

I`d like to know, when is the best time to sow potatoes to have some ready for Christmas?

[buildersmate]

This is far too unscientific for Earlies. A better answer is given by when: -
square root (average potato price per kilo at a basket of leading supermarkets) > [(no. of days of which more than 5mm of rain fall on the spuds) cubed + (average day length in hours / pi)]

[SKA]

my mum is growing some and she said after the plants have died you can dig them up!!

[Kos]

Wish me luck- I'm going underground tonight to sample my taters!!
I know that if you leave them there until the foliage has withered they will have grown to a decent size, but the purpose of my original question was that I want to capture them as 'new' potatoes.

[SKA]

if you pull them up too soon can you put them back in to grow bigger?