Hi,
This info might be totally wrong so.... just throwing it out there.
I saw lots of those videos too and tried it the summer before last. Planted some purple potatoes as always 4-6" deep in one bed and planted some 'Yukon Gold' potatoes in the first 1" of soil and just under mulch in another bed. Both grew just fine, Yukons plants got just as big as the purple ones. I continued to pile up mulch about 12-16" during the season.
Purple potatoes grew as always, not a great yield but pretty O.K.
About a week or 2 after the Yukons withered and turned brown I dug them up. There was nothing there except for pill bugs. I blamed it on the bugs. Not surprised. I had provided them the perfect habitat and a nice meal. But something kept nagging at me. The roots had been skinny, small and shriveled up (but still produced fine foliage!) but I saw no evidence of tubers at all, not even bits of the original potatoes I had planted.
So I did another online search. Don't remember the exact terms I used that day to describe this predicament. Found lots of those same videos again. But I found a couple of people that also tried it that might have provided the answer to my question. They both stated that potatoes are in the same family as tomatoes and share the same growth patterns, some are determinate and some indeterminate. And only one of these will produce tubers in mulch. Well, they didn't provide any specifics beyond that so... there it is. Maybe it's true, maybe not.
Most websites I have found discussing determinate/indeterminate potatoes don't mention this. But I am thinking of trying it again with a different variety. I mean.... it works for some people!
https://dengarden.com/gardenin...
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Happy gardening.
