When to harvest potatoes?

[Ouze]

Hello all,

This is the second year I've planted potatoes in fabric bags. I planted 2 varieties - Yukon Golds (100 days) and some red variety I forget the name of (110 days).

We're just about at 100 days now. The Yukon Golds have started to die, but they aren't doing so uniformly, some bags have plants that look pretty healthy along with some plants that are dead.

When do I go a-digging? Is it better to wait until every single plant in the bag is totally dead, or should I wait until they just start yellowing, or should I start harvesting now since it's been 100 days?

Obviously I want the best yield possible, and I'm not sure what the best timeframe is between "they still could have grown some more" and "they've started rotting".

Thanks!

 

[headfullofbees]

I like to eat potatoes when I have potatoes, and you'll have some now.
If you want to maximise yield, then cut the tops off the dead ones and wait. They shouldn't rot if they don't get too wet, or freeze.
I have been harvesting potatoes for 9 weeks and I'm much less than halfway through, even though we eat spuds most nights.
If all goes well, I'll still be harvesting in October.