Back in early January, when a week of bitterly easterlies cut across the country, I ventured out to Jersey to look over a potential project. We dipped sharply, through buffeting crosswinds, in a plane that was small enough to make the businessmen scream. I had never visited the island before, and it was surreal to see a landscape wrapped up in plastic and incubating the famous Jersey Royals. The earliest of the crop can fetch as much as £5,000 a tonne.
Last year I almost grew enough potatoes to go commercial. There were eight varieties in total and two rows of each. I’d been tempted by a combination of factors. We had space and it had been all too easy to click another variety that caught my eye on the online catalogue. Our new plot was also freshly turned from field, and potatoes are an excellent crop for “cleaning up” new ground.
Potatoes fall into three main groups: first early, second early and maincrop. First earlies mature after about 100 days, second earlies after 110-120 days, and maincrop after 130 days. If you aim to plant around Good Friday, selecting a range for continuity and keeping, you can give yourself salad potatoes and keepers.
Potatoes are easy to grow. If you have limited space you can grow them in a dustbin or pots on a terrace. In the garden they prefer ground that has been manured the previous autumn. They are not fussy about soil, but scab is alleviated if your soil is on the acid side of neutral and if water availability is regular. Water is important as the young tubers are developing – that’s why potatoes grow best in Ireland and Scotland.
Although you can plant shop-grown potatoes as mother plants, certified seed potatoes are virus- and disease-free, so they produce a higher yield. Chitting is advisable before planting – it speeds up establishment. It involves placing the seed potato end up in an egg box on a cool, bright windowsill to form “eyes” no more than a couple of centimetres long. A 30cm spacing between tubers is optimal, with rows 60cm apart, but wider spacing in the row produces a bigger potato, so the earlies are best planted closer for salad potatoes, and the maincrops, which you might save for wintry jacket potatoes and mash, can be spaced 45cm apart. As soon as the growth emerges above ground, you can start the “earthing up” process to keep the tubers from greening when exposed to light. Harvest can start as soon as you see the flowers opening.
There are about 400 varieties of potato, so start experimenting. Last year’s experience taught me this: you only need as many earlies as you can eat fresh out of the ground; and you need to choose maincrop varieties that will keep. We preferred lighter eating in the summer but came back to spuds for winter.
We had success and we had failure, as the blight caught the maincrops in August. Blight is a fungus, Phytophthora infestans, and it needs high humidity and mild temperatures day and night to grow on potato plants. Although I removed the foliage as soon as I saw the infection, it ruined a couple of varieties.
Generally I have chosen varieties that are blight resistant. Perhaps the best second early is “Belle de Fontenay”, with a smooth, waxy consistency. “Lady Christl” is another delicious first early, producing numerous disease-resistant pale tubers. “Orla” (first early) is the most blight-resistant early ever produced and is also good for second cropping.
“Edzell Blue” (second early) was hit heavily by blight last year, but the blue skin and the dry, tasty tubers were superb steamed and mashed or cooked in their jackets. “Shetland Black”, said to be one of the oldest varieties, is a fine jacket potato. “Pink Fir Apple”, a late maincrop potato, is delicious eaten whole and superb re-fried from cold. “Ratte” is similar but a little earlier. I have ordered “Sarpo Mira”, one of a blight-resistant range. I’ll let you know how I get on.
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