potatoes are pretty hardy and will grow in all sorts of soil or compost. just make sure that you keep the soil moist but dont over water otherwise the tubers may rot. also if you are going to have different varieties, put them in different planter bags and keep them away from each other to reduce the chance of Blight.
Good luck with them. There's nothing better than a home grown potato and the taste is so much better than those you get in a supermarket.
i am growing mine in the greenhouse using leftover compost from last years tomatoes - they are very healthy and will be ready shortly. Incidentally the bag I am using is one of the 99p shop green garden waste ones with a few holes I cut in the bottom.