Traditionally, seed potatoes are always chitted before being planted out but more recently, growers have queried whether this is necessary.
Chitting encourages the eyes on seed potatoes to start sprouting, thus giving them a head start for when they are planted out. Placing the tubers in a frost free place with plenty of light such as a window sill will cause the eyes to start sprouting. Each tuber has a more rounded, blunt end where most of the eyes are to be found. Place your tubers upright in a seed tray, or even an egg box, and wait for nature to work its magic. Within a matter of weeks, you can see the eyes sprouting. Once the tuber has two or three good-sized chits about ½” long, it can be planted out providing the ground is frost-free. Rub off any extra chits so that the growth is concentrated on those chits. If there is a danger of frost, ensure any growth is earthed up and covered to protect it.
First early potatoes particularly benefit from being chitted so they can be lifted within 10 to 12 weeks of being planted out, usually in June or July. There is some argument as to whether main crop seed potatoes benefit as they have a longer growing season. Potatoes will sprout and grow whether they are chitted or not. There is a theory though that chitting seed potatoes will increase the yield from each tuber by directing the plant’s energy into two or three shoots. Equally important, however, is preparation of the ground by adding plenty of well rotted manure, blood fish and bone or even chicken pellets.
For most vegetable gardeners, it’s that eagerness to get the growing season started, that means they will chit their seed potatoes.