A few weeks ago I picked up 10 large hessian sacks. These were originally used to hold coffee beans and have come fron both Brazil and PNG. They are quite large (about 1m wide when flat) and will hold a lot of soil. I rolled down the top and layered the bottom with a few sheets of newspaper to keep too much of the soil escaping out the bottom while still allowing drainage. Then filled the sack up with a good quality potting mix.
I've got two varieties to try. A 'Pink Fir' which I got from Diggers a couple of weeks ago and which is a little like a Kipfler. The other variety was called a 'Sapphire' and is a bit larger and a beautiful blue in the centre.
I've planted two seed potatoes in each sack, hoping they aren't too crowded. Now I just have to wait for the shoots to pop up. The beauty of the sack method, is as the shoots grow you just need to add more soil and slowly roll up the sides of the sack. Hopefully by the end of the year I'll have a nice big crop ready to eat!