CHITTING (Sprouting) PROCESS
It is very important that your tubers are kept in a frost free area. Spread them out in a cool, well ventilated place prior to sprouting (called 'chitting').
All seed potatoes, particularly Earlies and Second Earlies, can benefit from 'chitting' and the formation of strong 'chits' over several weeks gives faster growth and heavier crops when planted out. Use seed trays, shallow boxes or empty egg cartons to 'chit' your potatoes. You will notice that the immature 'chits' are all at one end (called the rose end). Place the rose end upwards. Keep in a cool, but frost free place in natural light. Sturdy 'chits' will form which should attain 25mm (1 in.) in length.
Potatoes grow best in rich soil containing plenty of well rotted manure or compost.
Planting times are not critical and are dependant on weather, soil conditions and regional variations.
Generally First Earlies should be planted 5 inches deep and about 12 inches apart, usually in rows 24 inches apart, in mid to late March. Second Earlies are planted in the same way in early to mid April. Maincrop varieties should be planted mid to late April, 5 to 6 inches deep and 15 inches apart, with 30 inches between rows. All tubers should be planted with the rose end upwards. Frost protection may be necessary.
Although the above refers to rows, Potatoes can be planted in large pots, grow bags or other containers, providing they have the right conditions.
Potatoes are hungry, and to ensure a bountiful harvest a high potash fertiliser can be applied at the manufacturers recommended rate.
You can incorporate fertiliser in each individual planting hole (it should not be in immediate contact with the tuber to avoid scorching), or you can incorporate it when planting and apply more when first earthing up. If you plant in a trench instead of dibbing or using a trowel, then you can scatter the pellets along the trench or leave until you earth up.
Most importantly protect emerging shoots from any frosts by carefully drawing soil over the shoots. Frost will blacken the shoots and delay production severely. First and Second Earlies particularly require plenty of water during prolonged dry weather especially when tubers are starting to form. Earth up regularly as the plants develop.
Start to harvest First Earlies as 'new potatoes' when plants commence flowering, although not all varieties freely flower or flower over an extended period. Therefore, a more reliable method is the number of weeks from date of planting. As a guideline, allow 10 weeks from planting for First Earlies, 13 weeks for Second Earlies, 15 weeks for Early Maincrops and 20 weeks for Late Maincrops*. Lifting times will also depend on the growing season, weather conditions at harvest time and the size of tuber you want. Tubers will generally become larger the longer their growing period. Maincrop varieties are usually left for at least two weeks after the leaves and haulms (stems) have withered, to allow the skins to set.
For storing varieties, leave the tubers on the soil surface for a few hours to dry and cure the skin before storing in hessian sacks or in paper in a dark, cool but frost free place. Avoid polythene as potatoes will 'sweat' and rot.
*The term ‘First Early’, ‘Second Early’, ‘Maincrop’ and ‘Late Maincrop’ refer to the time the potatoes take to mature, all crops can be planted at the same time and harvest will naturally be staggered by using different maturing varieties, see above for approximate durations.