All you need to do is put a couple of small potatoes in a pot of compost in the spring, add a bit more compost over the coming weeks ('earthing up' if you want the technical term) and then wait for the foliage to eventually die down. Admittedly, it takes a long time, but surely it's no worse than watching David Blaine sit in a glass box - and the end result is a lot more fun for the under 5s.
Today we enjoyed the big reveal. Our large plastic pot was tipped upside down on a flat surface meaning that all and the children could dig for the treasure together. Even with chronic neglect and inferior seed potatoes, our two spuds had turned into 35. Not a bad haul - and decidedly more useful than anything the Magic Circle has to offer.
Oh, and if you want to have a go next year, the Potato Council offers free potato growing kits to schools - just register here.
** Please note the contents of this blog reflect the views of its author and are not necessarily those of the RHS **