Last year my potato towers yielded fantastic results, considering they were made of tottering, flimsy old plastic flower pots with the bottoms punched out.
This year, I got free 12x36 boards and made three 36x36 potato towers! The potato plants grew enormous before I even had the chance to frame the towers around them. I surrounded each plant with the first 12-inch-tall board for layer one, and filled them with 12 inches of soil rich with well-rotted manure. I lined the insides of the towers with chopped comfrey and borage as green manure.
The potato tops were covered completely by soil. Now, two weeks later, I am anxiously awaiting signs of resprouting, but nothing yet. I know it will take time for the new sprouts to emerge that far up, but I just want to reaffirm that I haven't killed them by over-burying!
Location: west marin, bay area california. sandy loam, well drained, acidic soil and lots of shade
posted 5 years ago
I wonder if the comfrey and borage got hot and hot composted and it cooked the potato plants? you could try digging down some and looking for them. i never bury my plants completely I always leave some of the green part sticking out so it can keep getting food from the sun. I am an extreme novice so I don't know if that is the right way to do it but it seems to be working well.
When hilling up you don't want to bury the entire plant. Leave the top few leaves exposed and then add new soil as they grow. You really want to do this as the plant is growing, adding soil, leaves, compost, hay, etc a bit at a time. Burying older established plants doesn't always result in more potatoes. Once the stems have developed, had exposure to sunlight, and developed fibers for strength they are stems and wont grow more roots and thus potatoes even if you cover them. For these towers to really work you have to keep burying the new growth. When they're really going strong I add more cover material every couple of days. Lots of these towers really just grow potatoes on the bottom 6-10 inches and nothing above that. Mostly because it's not as simple as the internet makes it seem.
I've tried different tower methods but these days don't bother with anything more than about 2 ft high. Higher never seemed to increase my yields and was just more work for almost no gain. I only 'tower' the late season varieties. Potatoes just like tomatoes have determinate and indeterminate types. Only the indeterminate types will grow potatoes all the way up the stem. The determinates (which many early varieties are) will set new potato buds all at the same time and once they are done it doesn't matter how much more you hill them up...you may get more roots along the stem but there will be no more new potatoes.
I'm not sure if a completely buried potato plant will resprout and even if it does I don't think your chances of getting a tower of potatoes is good. If I was you I'd dig down and see if there is anything surviving under all that soil and comfery. If you do find the original plant expose the tops and let them grow out from that level. I wouldn't try to keep burying them any more at this point.