Silly question about how Potatoes grow!

[peanut]

I know this is a daft question but when Potatoes grow, you place the seed potato (in my case in a compost sack) on the compost and fully cover with, as shoots grow you earth up.
Ok so my question is are the new pots grown on the upward stem growth or do they grow below the seed potato?
I'm wondering how much compost I should place underneath the seed pot.

Thanks

[shirlthegirl43]

I think they grow off the stalks that go up from the seed spud to the surface - that would explain why there is a danger of them appearing too close to the surface and going green. I plant my seed spuds on about a half inch of compost at the bottom of the bucket then earth up as the leaves grow.

[peanut]

Thanks Shirley,
Glad you understood what i was trying to say! I now have just enough compost to plant a few more spuds, I hate having to go out for compost when I've already started pottering about!

[Alice]

Peanut, I put about 4" of compost in the bottom of the bucket and mix in some 6X or something as this is the root run for the potatoes .

[Geo]

Here you go Peanut...



Geo..

[peanut]

Geo! What a star you are, you should be a teacher!

So I guess then the more i earth up the better the crop I might get. I've put a few inches on the bottom then covered up the spuds 2/3 depending on the size of the sack.
Hopefully this should be ok, only thing is the lovely old man nextdoor who gave them to me can't remember what variety they are! He said they are a new potato one that was introduced a year or two ago! Any ideas?