Just a quick video showing how I grow a few potatoes in the polytunnel in containers for an extra early crop. I use a really fast maturing first early potato such as Rocket. Then simply add 3-4" of compost to a pot or a container,add a little fertilizer and than place your seed potatoes on the surface. As a general rule use one seed potato to about every 15 litres of pot size. Then cover with another layer of about 3" of compost. After a couple of weeks the shoots should emerge and then just keep filling the pot up with compost leaving a few inches of the leaves visible as they grow until you reach the top of the pot. I cover with bubblewrap initially as it helps to keep any warmth in the soil. Cover with fleece or similar if a frost is forecast. Hopefully after 70-80 days or earlier you should then have some really early new potatoes,much earlier than you would growing outside. Website : http://www.allotment-diary.co.uk Facebook Page : https://www.facebook.com/pages/Allotment-Diarycouk/119640048156011