Mid February is a good time to start chitting seed potatoes. Put simply, chitting is the process of growing shoots (chits) to give the potatoes a headstart and crop earlier than they might otherwise do. Put the potatoes with the end where you can see a number of 'eyes' uppermost in an eggbox on a sunny windowsill or in a sunny porch. The shoots that grow will be knobbly and purple/green and completely unlike the long, pale shoots which grow on potatoes left in the kitchen cupboard for too long.
Once the shoots are 2 to 2.5cm (3/4 to 1") long and the risk of frost has passed, the potatoes can be planted out. Dig shallow ridges of soil 45-60cm (18 to 24") apart and plant the seed potatoes into the ridges 12cm (5") deep and 22cm (9") apart.