Blog – Your seed potatoes have got their eyes on you!

Or at least they should have! Potatoes are easy to grow, and every time you unearth one of these golden gems, you’re filled with motivation to dig for more. It’s addictive. They do equally as well in containers and raised beds as in the open ground and are fairly simple souls that don’t ask too much of us. They’re useful for breaking up ground that hasn’t been cultivated. It’s now time to purchase seed potatoes and ‘chit’ them. Just to note -I couldn’t get mine from my usual supplier this year. It seems I’m not the only one that’s going to be growing them!

An eye watering choice of ‘seeds’ usually appear in garden centres in February and March. The term ‘seed’ refers to a potato tuber that is grown specifically for planting so that it produces a new plant. The new plant will ultimately produce more potatoes. The potato plant stores its energy in the tuber so that it can regrow the following year. In spring, potato tubers will start to sprout new growth from growing points called eyes. Each potato has several eyes.

Although the potatoes in your fridge will start to sprout if you keep them too long, it’s better not to plant them in the garden because they could be contaminated with blight spores and viral diseases.  It’s also not advised to let leftover potatoes (volunteers) to sprout in your vegetable garden for the same reason. The new seed potatoes you purchase every year are guaranteed to be free from viruses.

When you bring your babies home, they need to be allowed to form new shoots from the eyes. This is a process called ‘chitting’ and the shoots are referred to as ‘chits’. Chitting isn’t a vital process but it will give your plant a head start once planted in the ground.  Putting the seeds into a recycled egg box on a cool windowsill for several weeks will encourage the chits to grow.

At least two or three of the eyes of the seed potato need to be free to grow upwards and outwards.

Once your potato tubers have grown shoots that are about an inch long, and providing that the long- term weather forecast is favourable, you can plant them in the ground / containers in March or April. They like a sunny, well drained site in ground that has had manure dug into it during the winter. They prefer slightly acidic soil (which is why they grow so well in compost heaps), but it’s not imperative. You can plant either in holes or trenches at least 6 inches deep. Plant each potato 15 inches apart and plant rows of potatoes with an 18 -inch gap between them.

Getting the spacing right is important because throughout the growing season you are going to do something called ‘earthing up’, and for that, you need plenty of room.

 As the tall stem (haulm) of the plant grows, you need to keep building up the soil around the base of the plant. This seems counter intuitive but the plant develops the potatoes under the soil. The more the haulm is buried the more it will grow. The more the haulm grows the greater the opportunity it has to develop potatoes. This process is known as ‘earthing up’ and is a way to maximise your yield.

Earthing-up can be achieved with materials other than compost/soil. The aim is to keep the spuds under cover because when they are exposed to light, they become green and inedible (seriously – don’t eat green potatoes!). You can use straw, shredded newspaper and grass clippings  that will all rot down and feed the plant. Grass clippings are ideal. Potatoes need nitrogen to grow their haulms and this is found in the grass clippings. The more clippings you add, the larger  the haulms should become which maximises your yield even more. Keep ‘earthing-up’ and ensure that any potatoes that might start to peep through the soil are quickly covered to reduce their exposure to light.

Now, you know that family doesn’t always get on and so potatoes should NOT be planted with tomatoes. They also don’t like to be near cucumbers, peas, strawberries, turnip or spinach. They get on well with members of the brassica family such as cabbages, cauliflowers and Brussel sprouts and also with beans and lettuce.

Keep your spuds well and evenly watered. It takes a lot of energy to grow these marvels. Give them a nitrogen rich feed while they are growing the haulms. Afterwards, feed them something rich in potassium to help the development of the tubers. When growing in pots, take careful note of watering. When it rains it’s easy to assume your pots will be well watered. These fellas are growing near the base of your pot and you need to ensure that water is reaching so far down. You may have a poor yield if not adequately watered.

First early varieties are less likely to be damaged by pests. If planted in March they should be ready to harvest in June. Harvest second earlies from the end of June to the start of August. Maincrop potatoes are probably the most recognisable varieties and they store well. Harvest maincrop potatoes from August. After the foliage has died back, you can harvest them but leave them on the surface of the soil for a couple of days for the sun to dry the skin, this helps them last longer in storage.