When you’ve got a greenhouse you’ve got everything you need to be productive in terms of homegrown fruit and vegetables. Whether you are starting out, or an experienced gardener, growing potatoes is one of the easiest and most rewarding crops you can grow. With a greenhouse you can get your potatoes off to the best possible start as early as January.
A quick visit to the garden centre in the New Year should reveal a whole range of plump, pert seed potatoes complete with information boards. Potatoes aren’t actually grown from seed, even though what you buy are called seed potatoes. Instead you buy special, virus free potato tubers that are planted when the soil starts to warm up in mid March or April. Find a garden centre that sells the potatoes loose, so that you pay for the weight of what you choose. That way, you can select two or three tubers of any variety you want to grow or more if you want to. If you have a large garden the prepacks of one variety may be better value.
If you have a frost-free greenhouse there is no reason to delay in buying your seed potatoes, and the earlier you get them, the better choice you will have. You may also be lucky to have a special potato day locally where you can buy rare or unusual seed potatoes to try.
If you’ve never grown potatoes before then the best type to start with are what are called ‘First Earlies’. These potatoes have been bred to mature earlier than the usual Maincrop varieties and will produce lovely, small to medium, new potatoes. The plants don’t tend to grow as large as Maincrop potatoes and are ideal for small gardens or for growing in containers. To give them the best possible start you need to chit them. This just means that you need to put your seed potatoes in a light, totally frost free place to sprout. It gives them a head start before they are planted. A cool greenhouse is ideal.
Unpack your potatoes carefully as soon as you get them home. Lay them out in trays or egg boxes so that they are not touching. Usually one end of the tuber has more ‘eyes’ or sprouts developing, this is often the blunter end and is sometimes called the ‘rose end’. Ideally this needs to be exposed to more light so where possible look for the blunter end of the potato and position each potato with this pointing up. This allows the sprouts to develop. It is absolutely essential that the potato tubers are protected from frost, but they also need good light to develop. I usually place mine in old egg box trays on top of a polystyrene sheet to insulate them from cold below. Then I keep a ream of horticultural fleece handy to throw over them when a cold snap threatens. Make sure you remove it when the danger has passed and check your tubers daily.