The history of the potato is a remarkable one and surely warrants further exploration at a later date. But is it worth growing at home? If one potato is much the same as the next to you, then probably not, because they are so cheap to buy. But if you love your taties and can tell the difference between varieties, then of course you will be growing them. And the message from the Head Vegetable Grower here is that if you want new potatoes for Christmas dinner, you will have to get them in this very weekend because most early varieties take from 75 to 90 days to mature, though Swift and Rocket can do it in 60 days. Potatoes are vulnerable to disease so it pays to start with fresh certified seed potato from garden centres each year rather than using your own old potatoes which are shooting.
Potatoes are heavy on space. Because this is not a problem for us, we do them in rows digging narrow trenches about 20m deep and wide (full sun, well cultivated friable soil, fresh ground if possible), piling the soil to the side of the trench. The potatoes are then laid on the bottom of the trench and covered with 10cm of compost. As the shoots reach about 20cm, more soil is layered on top – a process called mounding. The potatoes form on the stems so you need to encourage stem growth and keep a thick enough layer of dirt to keep the potatoes well covered and stop them going green. The mounding process continues until the plants have flowered and it may be necessary to water in dry spells because the mounds lose moisture.
In smaller spaces, the stack of tyres is a popular technique, though hardly aesthetic. Potatoes need good drainage so it is better to build your stack on dirt rather than concrete. Start with one tyre and fill with good soil or compost, making sure you fill the rims as well. Plant about three potatoes and, as mounding is needed, add another tyre and fill with soil. You will probably end up with a stack of 3 or 4. If you plan to use potting mix instead of soil, they will become expensive potatoes.
One of the reasons for getting potatoes in now is to try and get crops through before the dreaded blights hit. In our experience, if you are not willing to spray your potatoes regularly with copper (about every fortnight), unless you know what you are doing, get your crop in early and manage them very well, you will get disease. Don’t use nitrogen based fertilisers as they are a root crop. Favourite early varieties here are Liseta and Jersey Benne, for main crop Red Rascal and Agria.