As soon as the potato tubers have been delivered you should unpack them and start the chitting (sprouting) process. Place them in single layer in a seed tray without compost and leave in a light, cool area protected from frost. This can be started about six weeks before you intend to plant them. Early varieties can be planted out under frost fleece protection, but the later varieties should be planted after the worst frosts have passed in your area - this is generally mid March to mid April. Dig a trench 8 - 13cm (3 - 5in) deep adding a general purpose fertiliser to the bottom of the trench. Plant the potato tubers in the trenches about 30cm (12in) apart, being careful not to knock the shoots off the tubers, and keeping the shoots facing upwards. Then lightly cover with soil. As the plants get to around 20cm (8in) tall you need to bank up the soil around the plant, so the soil covers the bottom two thirds of the plant. Watering your plants well will help improve crop yield and discourage potato scab.