What is a potato?
It is a perennial herbaceous plant grown for its swollen, underground stem tubers. It originated from the Andean highlands where it was cultivated by the Incas for over 2,000 years. Spanish explorers brought the potato to Europe in the 16th century, since then it has been grown here as an annual plant.
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Variety is the spice of life
There are so many wonderful types of potato to try, floury ones are good for mash and waxy varieties are best for salads. Potatoes can be planted from the early spring by starting with the early cultivars.
How to grow your seed potatoes
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Early potatoes mature in a about a 100 days, planting them out from mid March (when the hard frost has past) until the end of May.
Second earlies take 110 to 120 days, and the maincrop planted from late spring needs 125 to 140 days before harvest depending on the weather.
In the ground - plant the potatoes in trenches or individual holes 7-15 cm deep (depending upon the size of the tuber) and space them out approximately 30 cm apart with about 40-50cm
between the rows. Plant the tuber upright so that the shoots are at the top, then cover them with at least 2.5 cm of soil. When the green stems of the plants are about 20 cm tall use a spade to draw up more soil around them (earthing up), this prevents exposing the tubers to light which would make them green and inedible.
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Watering the bigger the plants the more the water, give them a good soaking. Organic liquid feed applied before the plants are established also helps if manure was not added to the soil before planting.
See Garden Organic's advice here.