Growing the best organic potatoes
The best potatoes that you will ever taste are ones that have been grown in either your own homemade compost or a soil enriched with lots of bulky organic matter such as well-rotted farmyard manure. Here are the most important things you need to know in order to be successful with spuds:
Potatoes are hungry and thirsty in equal measure.
They will benefit greatly from a soil that is also rich in potash.
It is highly likely that they will suffer from potato blight and it is entirely possible to overcome this without losing the crop.
Let’s deal with these one by one.
Firstly whether you are growing in your garden soil or in a big pot (which they grow well in by the way) potatoes need plenty of food. They also like water. The organic matter that you add to the soil will help conserve moisture but the bottom line is this – if it is a dry season with no appreciable rain you may need to water the crop every two to three days from the time it is in flower. This is the time that the tubers are beginning to swell underground.
Secondly the potato family, which includes peppers, chillies, aubergines and curiously tobacco, is beloved of potash or potassium in its mineral form. The two best ways to access organic potash are through wood ash from fires and comfrey.
No organic garden is complete without a comfrey bed. This is a plant that sends its tap root very deep to bring up and store in its huge leaves much needed trace elements and potash which, when composted, will be released to other plants. In this case potatoes.
Thirdly it is likely that your potatoes will suffer from the deadly potato blight (Phytophtora infestans). Although this fungal disease is capable of ruining the entire crop the good news is that there is a means of combatting it before it can take a hold. Once it is in the crop it is very difficult to reverse its progress. However regular applications of a liquid ‘tea’ made from the mare’s tail plant (Equisetum arvense) will prevent the fungus from taking a hold. It is not a cure, it is a preventative. I have been using this tea for years and have no trouble with blight. Even in the wet season of 2012 when it rained all summer and blight hammered everyone’s potatoes, my crop was untroubled.
This is down to personal choice and is best figured out from the position of how you like to eat your potatoes. In our family we like potatoes that roast well. For that we need a potato with a fluffy interior, or what’s known in the trade as ‘high dry matter content’. But those types wouldn’t make great chips for example because they are too fluffy whilts they would make good boiled potatoes. The qualities of each potato variety are highlighted in the catalogues. We also like salad potatoes such as Ratte and Pink Fir Apple. These have much less dry matter as they are often eaten cold as salad or fried up (the origin of the name French Fries!).
New varieties are being bred all the time and it is interesting that some of the really old ones have stood the test of time and are still available like King Edward VII, British Queen and the Maris and Pentland types. I don’t stick to any special variety except for Pink Fir Apple which I have been growing for years, saving my own seed each year. I do like to grow early or ‘new’ potatoes because there is nothing like the taste and the texture of them when boiled with a little mint and served with butter and salt and pepper.
Preparing for planting and chitting
Readying potatoes for planting by ‘chitting’ them out is a wise move, one that will speed things up once they have been planted. It is the process of encouraging the potatoes you are going to plant to produce shoots before they are planted. In the spring when you buy potatoes for eating or you have some left over in a sack you might notice the shoots beginning to appear from January onwards. The idea is to encourage this by placing your seed potatoes in a cool, dry, frost-free, light-filled space, sitting upright in an egg box or seed tray so that this can happen quicker. Its important to put them the right way up and you can tell this because on the bottom of each potato is a small indentation where the tuber was joined to the plant when it was growing. This needs to be facing down. Also on the tuber are found ‘eyes’. These are also indentations shaped like a new moon. These must be pointing upwards and it is from these that the new shoots will emerge. By the time you come to plant in March or April the tuber will have several well-formed clusters of shoots. Another way to be sure of the right way up is to notice that the bottom of the potato has a small dimple with some shrivelled fibres where it was once attached to it’s mother plant. This dimple should be facing downwards at planting.
Manuring and planting
Once you have decided on the size of your bed you can get fertilising. The old fashioned way was to dig the manure or compost under the topsoil so that the potato roots travelled downwards for their feed. Nowadays it has become acceptable to lay the compost or manure on the surface of the soil because we are feeding the soil not the plant and therefore it matters less where precisely you put the fertility.
In the garden each potato plant needs a foot or 30cm square of space, i.e. rows should be 30cm apart and there should also be the same between plants. Potatoes need this amount of room not least because you are going to ‘ridge them up’ once they have started producing leaf.
In containers you can grow them slightly closer together, a 20cm spacing is ok, and it won’t be possible to ridge them up and his won’t matter as long as there is a good depth of soil in the container for them to root into which is the purpose of ridging up.
My favoured way of planting in the garden is to use a trowel to dig out a planting hole about 15cm deep. Put the potato in with the shoots facing upward, return the soil to the hole and firm it in with your knuckles or your foot without stamping.
The idea behind ridging is that it gives the potatoes space to grow into. It also happens to be a good means of controlling weeds and can act as a protectant against frost. Once the foliage is very visible above the soil surface you rake the soil up against the foliage so it is almost covering it. It wont matter if you bury the leaves as the progress of the growth of the spud is unstoppable.
You can carry this out twice or even three times as the plants grow and the foliage expands. The only exceptions are the salad potatoes such as Pink Fir Apple, Ratte and Belle de Fontenay (there are plenty more salad types, these three are my favourites), theses are supposed to grow on the flat – no ridging please.
So when are the spuds going to be ready? I always plant my earlies on or around the 15th March. It is my mother’s birthday and the day of Ceasar’s demise. The Ides of March. I give them around 85-90 days to mature. I get so excited by the thought of the first new potatoes I very often end up digging them too early when they are still pebbles.
For all the bad press potatoes get these days for their high carbohydrate content and all the clichés around chips and fries, the reality is they are extremely good for you being, amongst other things, very high in Vitamin C.