Many a novice potato grower has been asking the question: “When do I plant Potatoes”. The short answer would be to plant out your potatoes as soon as they are finished chitting/sprouting – and there’s no frost in the ground.
In the southern parts of the UK this usually means mid-March, while in the North/Scottish borders it’s about early to mid April. This also depends on altitude – the higher up you live – the later you can plant your potatoes.
The potato haulms (stems and leaves) are very frost sensitive, so as long as there’s even a remote chance of night frost you need to keep them protected, or you run the risk of losing your crop. You can do this by “earthing up”, so any new shoots are covered over by soil at all times (don’t worry, they will always grow back).
The other option you have is to keep the potatoes covered by a heavy duty clear plastic sheet, which will act like a greenhouse, and ensure an earlier harvest. Also you can use horticultural fleece/garden fleece or garden cloches for this purpose.
As long as you keep your potatoes growing, and absolutely frost free, you should be able to dig in to a nice fresh helping of new potatoes in 6-8 weeks time.