The post I wrote on growing potatoes in containers last September is currently attracting quite a bit of traffic, reminding me that I promised to round up the advice of bloggers who'd had a go at growing 100 lbs of potatoes in a 4 foot square container.
Just to recap, the idea is to earth up potatoes as they grow, with the idea that the plant will continue to produce stolons (and therefore potatoes) along the length of the stem, filling the container with potatoes at all levels. Results have been, almost without exception, disappointing, with potatoes at the bottom of the container, where the seed potato was placed, and a lot of empty soil above.
But... Let's revisit Phillip Cairns at Mudsongs. He had a go three years running, honing his methods but without great success. Last September he wrote to me: "If we don't get good results this year, we're done trying. We'll update the page on our website if the mini potato tower is successful (though we have our doubts)."
Well, go and have a look! Against his expectations, he harvested 33 lbs (15kg) of potatoes, double his previous year's yield. He says:
Many of the potatoes we harvested from our mini tower this year grew near the top of the tower just below the surface of the soil (and most of them were large potatoes), which seems to indicate that the potato tower hilling process actually works.