A row of potatoes being covered.
Young plant almost ready for earthing up.
We also know that potatoes are supposed to be chitted – got ready for planting – and that they come in different varieties depending on how long it takes to make a tuber. That represents all there is to be said for potatoes in a way – but as ever, there is more to it than that.
BEAT THE BLIGHT
Your battle against blight starts now, in January, when you are preparing to buy your potatoes. By the way, now is the time to get your tubers (called ‘seed’ potatoes, but they are not seeds) on order from the catalogues.
Always buy fresh rather than keeping back old ones, which are often contaminated with either a virus or fungi. You will always get a better crop that way.
Before you buy your standards, look back to last year – which was a very blighty year – and think about which varieties you grew. We sometimes stick to our favourites when new varieties are out there to be tried. It seems, like roast dinners, we are very traditional about our potatoes, and find it hard to change – the same can be said about tomatoes too, for that matter.
These varieties are listed in order of their resistance to blight:
* Sarpo mira
This Hungarian variety is a maincrop and is all but completely resistant to blight. The leaves are a little more susceptible than the tubers, and you can almost be guaranteed a good crop.
It is a maincrop variety taking about twenty-two weeks to produce a crop.
A bit like Maris Piper – if you like chips. It is another maincrop potato that has good (but not perfect) blight resistance – a million times better than Piper though.
Great for roast potatoes, and can be left for a long time in the soil. It has reasonably high blight resistance.
A great all-rounder – fairly good a beating the blight. These are super potatoes.
EARLY OR LATE
The time needed for the plant to produce a reasonable crop is important.
‘First Earlies’ need around 12–15 weeks, depending on where you are in the country. ‘Second Earlies’ need 17–20 weeks, and ‘Maincrop’ need 20–25 weeks.
Get your Earlies in the ground by St Patrick’s Day (17th March), and by June you will have your first crop, and wonderful it is too!
‘First Early’ varieties:
Maris Peer, Home Guard, Arran Pilot, Pentland Javelin, Rocket, Pink Fir Apple.
‘Second Early’ varieties:
Kestrel, Wilja, Estima, Osprey, Nadine.
Admiral, Cara, Eden, Maris Piper, King Edward, and all those in the list of blight-resistant varieties above.
Preparation of the soil is important. It must be like a sponge, full of well-rotted organic matter. Potatoes need a lot of water, but apart from emergencies this water must come from the soil itself. Incorporate as much organic matter as you can some weeks before planting – even during the previous winter. The saying, “A spade dug before Christmas is worth two after,” is quite true. You are trying to give the soil time to rejuvenate after the last crop, and also the digging. Whenever you dig the soil it always loses some fertility – but then always gains it back again – with some more – for some weeks after digging.
This is the process that takes place naturally, though I think we have got ourselves somewhat distracted by it all. For me, potatoes evolved under the ground, and that is where they should be. The idea of chitting is to leave the potatoes on a tray, in an airy place. The plants send out shoots, and as the starch in the potato is converted to sugar, it becomes soft.
Some of this process is triggered by light, and some by the presence of water.
Certainly, by the time the shoots are growing, the plant needs water, and by leaving them in the dry we might be doing them harm in the future, particularly in their immune systems, which will have some bearing on their ability to withstand blight.
The BBC programme, Gardeners’ World conducted a trial to see if potatoes did better chitted or not – their results showed no actual difference, but I do wonder how the trial looked at blight resistance – it might not have been a blighty year that year, so more work needs to be done.
It is possible to grow potatoes anywhere so long as you stick to three rules:
* It needs to be very fertile.
* It needs to be moist but not soaking wet.
* The potatoes need to be in the dark.
I dig a trench, mostly a spade deep by around 10m long. Basically, you lay your potatoes in the trench, eyes uppermost, and cover.
Earlies should be spaced 45cm (18in) apart, and Maincrop 75cm (2ft 6in) apart. Maincrop rows should be 75cm (2ft 6in) apart, and Earlies rows should be slightly narrower.
The plants will peep out of the ground by the end of March and you should cover them by drawing soil over the stems. You are looking to turn your row of potatoes into a Toblerone shape, about 45cm (18in) high, inside which your potatoes will develop.
Potatoes exposed to light become green and consequently contain a high level of alkenes, which will at best give you a tummy upset – at worst make you quite ill.
If we have a rainy summer, they do not need watering, but will grow long vines. I remove the flowers and feed them with some home brew fertiliser a couple of times. If you have to water them yourself, it means the weather is hot, so only water at the soil level and do not wet the leaves.
By the time a crop is ready to be taken, I remove the vines and burn them – I never compost potato vines.
Using a fork, dig away from the vine, and lift the tubers out of the ground. Start from the outside of where you think the tubers are and get beneath them. This is why we talk of ‘lifting’ the potatoes. When you have the majority of them, dig deeper to remove all the tubers, no matter how small – this is important because those left in will grow next year – possibly ruining whatever crop you have put in; they may carry disease too.
Leave the potatoes in a dry but airy place, out of doors, to harden off. This is sometimes known as ‘curing’ the potatoes, but it is a bit of a misnomer. The longer they dry the better.
I always store my potatoes singly on shelves in a dry shed. This way they do not touch each other, and if one potato goes bad the rest are not affected. I once stored them in an old bath, and within a month they were all black and messy. I was heartbroken, and I take better care of them now.
There are so many diseases and parasites of potatoes that it is best if you do not grow potatoes on the same piece of land for four years. This way many of the problems will have been removed, and you will get lots of other crops. I go for another root crop – carrots and turnips, and then beans or maybe brassicas. There is a bit of a problem with adding lime for brassicas and then growing potatoes shortly after – consequently, you need some space between the two crops.
Hopefully, next year will be great for spuds – don’t you just love them!