A few things about growing potatoes, they do not grow from true seed but rather re-grow from vegetative parts, in essence they re-grow form the potato itself. Any potato can be used to propagate however it is recommended to use certified seed potatoes as they have the best chance of being disease free.
You can plant the whole potato or it can be cut into pieces. When the potato has been cut leave it for 3-4 days to let it heal over otherwise it will only rot in the ground, they can also be dusted with garden sulphur this will be additional protection against rot. The more eyes the potato pieces have will produce a smaller but plentiful yield and if you plant larger pieces with a few eyes this will produce fewer but larger potatoes.
To give your seed potatoes a head start you can *chit them, this is a term for letting the potatoes form nice green sprouts by putting them in a cool and bright (not a hot sunny area) place. You have probably noticed potatoes that have been left in their bag have grown long faded yellow sprouts, these are weak sprouts and are not recommended for planting. *Note: Chitting is done before cutting and healing.
Planting in the ground:
Dig a trench 6 inches deep and amend with organic compost lay potatoes eyes up every 9 inches and cover with soil. Once you start to see the shoots approximately 8 inches above the ground hill or mound the soil over them. Water well especially when there is a lack of rain. *Note: rotate your potato crop every few years to decrease the risk of disease.
Planting in containers:
Start with a 25 or 30 gallon pot approximately 24” to 30” in diameter your container should have good drainage. Add 2-3 inches of a good potting soil mixed with some organic compost, lay your seed potatoes’ eyes up and cover them with another 2-3 inches of soil compost mixture.
When they have sprouted about 4 -5 inches cover them up again with your compost soil mixture, keep doing this until they reach the top of the container. Potatoes’ in containers dry out faster than in the ground so remember to water well reaching all the way to the bottom of the container, you can also add a slow release vegetable fertilizer too. Make sure you are able to move your container in the heat of the summer, try putting your container where it will get sun for 6 hours and then shade over in the afternoon to keep them cool.
Harvest and Storage
Harvest when the plants have turned yellow and died back. To store for the winter you will need to cure your crop (this toughens them and extend their shelf life ) by spreading them out unwashed in a cardboard box for a few weeks letting air circulate and stored in temperatures between 10ºC – 15ºC. Store in a well ventilated container in a cool dark place with humidity levels of 80%. Note: before storing inspect your potatoes for bruising and rotten spots,continue to do this throughout the winter months so any rotten ones don’t affect the rest.