Hi Bruno2,
The biggest crop will be had when all of your vegetation is dead,brown,withered,almost to the point that you can't remember where you planted them, .....
That said, I don't have the time or patience for that ;-)

I would make a terrible VULTURE , I could never wait for something to die, I would go out and kill it ;-)

So, anyway,,,, after about 90 days or so, I would reach my hand down and pull out some wonderful "new potatoes", you don't have to ever kill the plant, just reach down and take whatever you want,whenever you want it.

Have fun and report back (with pics ;-)

Check out my video (link below) you can see how early I harvest ;-)

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Here is a link that might be useful: Potatoes in the Garden Bed

I agree that for final harvest, especially if you plan storage, all the above ground foliage will be dead and brown and gone for the most part just as Jon described. If you dig up a potato then and rub it the skin on an unfinished one will be thin and easily rub off with your fingers. Wait another 5-7 days and check again. Wait for the skin to thicken up and then dig them up, cure, dry and store.

Dave

Jon! Glad you responded. I stumbled across your video on planting potatoes yesterday. You planted them a lot closer than the papers that came with my seed potatoes recommended. They said something like rows 3 feet apart. I don't have the room for that! Are yours closer because it's a raised bed? How much room do they need underground?

Yours look amazing!

Kim

Hi Kim,
As long as your soil is loose they can be within 1' of each other in all directions, my beds do allow me to plant closer to each other because there is no compaction, and because the soil is so loose they are free to expand at will.

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