Spuds 'R' Us

The common 'Spud' (slang for: Potato) was first discovered in Bolivia, South America in the Elizabethan era, arriving in an area of Spain around 1570.
It was first discovered growing at high altitude where it was very cold and snowy. They survived mainly because of the hairs that covered the foliage which gave them a protective shield not just from the cold but from diseases such as 'Blight'. However, because of cloning, potatoes changed not just their variety but also the appearance of their foliage, which has made them more susceptible to pests and diseases. Breeders are trying to clone potatoes so that hairs are clearly visible on the foliage to give them protection, but this will take time.

By the 18th century, the potato was a common sight in allotments and gardens, and were said to be 'wholesome and sustaining'.

When the potato did end up in Europe in the late 16th Century, it was given the botanical name Solanum tuberosum, which belongs to the same family (Solanaceae) as the common Tomato and a variety of other plants such as Solanum and Datura, ornamental plants which are still used for medicinal purposes but can prove fatal in the wrong hands.

The potato has proved very useful in both world wars when food was scarce, and even now is still a favoured vegetable at the dinner table.

Buying Seed Potatoes and Chitting

Due to the hot dry summers that we have had in recent years, seed potatoes can be in short supply and so buying early is essential, especially if you would like a particular variety.

They appear in most DIY stores and garden centres during January, usually when the weather is cold.
When choosing potatoes, it is worth checking to make sure that they are in good condition and there are no soft or ill-looking ones in the bag. Ideally, the eyes (small shoots) should be no more than 1 cm (10 mm) long, but this does depend on the month you buy them in.
Always read about the variety first, so that you know what they are suitable for and the particular type (see below).

Here are the different types available
¹:

• First Early - These can be planted when the ground warms up and frosts are a distant memory. They are usually planted from late March onwards and will be ready to harvest in June/July. These are the best if you suffer from Blight problems, as they are usually harvested before the fungal spores of Blight take hold.
• Second Early - These can be planted early to mid-April and are usually ready to harvest by July/August .
• Early Maincrop - These can be planted in mid to late April and harvested in August to September.
• Late Maincrop - These can be planted in late April and harvested from September onwards.

When you get your potatoes home, they have to be started off in a frost-free place such as a shed or garage. This process is called 'Chitting', which gives them an important start to get the tubers (potatoes) shooted before planting.

If you look at each potato, you will notice they all have little shoots growing from the eyes of the tuber. To encourage them to shoot, they need to be stood up-right in either egg boxes or seed trays with the eyes pointing towards the light. You usually start the Chitting at least six weeks before you intend to plant them.

It is important that they are kept in a frost-free place, otherwise the shoots will simply die off, causing the potato not to do its best once planted into the ground. If you find there is going to be a late frost or cold spell and they are in the shed or garage, it is best to cover them with fleece, doubling it over to keep them snug. Only use fleece, never plastic, as this will cause them to sweat which could rot the potatoes.

Planting Into The Ground

It is best to rotate the crops each year to kill off any pests which attack the specific vegetable, the recommended time not to plant potatoes in the same spot is seven years. This is not always practical, so it is possible to cut it down to four years, after which time most of the pests in the soil should have died off.

Potatoes enjoy full sun and like heavy soil because it is full of nutrients, and kept moist. It is always best to incorporate some well-rotted matter such as manure. This should be mixed in when the ground is dug in the autumn time and also put into the trench before planting.

When there is no sign of frost and the ground has warmed up a little, is the best time to get planting.

Plant Early and Second Early Potatoes 30 cm (12 in) apart at approximately 10 cm (4 in) deep in rows 40-50 cm (16-20 in) apart.

Maincrop Potatoes should be planted 37.5 cm (15 in) apart at approximately 10 cm (4 in) deep in rows 75 cm (30 in) apart. (This rule applies to both Early and Late Maincrops).

Plant your chitted potatoes into the dug-out trench with the shoots pointing upwards, being careful not to break any off when standing them up. You will be able to get them to stand up better by digging a small hole with a trowel at the bottom of the trench, after digging in well-rotted matter.

Cover the potatoes lightly with soil so the trench is completely covered, and water if the soil is very dry, remembering to place a cane or piece of wood at either end to label where the potatoes have been planted. Also remember to write a label so that you know exactly what variety is where.

Earthing Up

When the shoots start to appear, it is time to 'earth-up'. This involves either raking or digging the soil from the edges of the trench to build up a mound over the emerging potatoes.

This needs to be done at regular intervals until the mound is approximately 15 cm (6 in) high over each trench. It is essential to do this to protect the potatoes, and to stop them from turning green: they are then poisonous to eat.

Harvesting

Depending on type and weather, harvesting usually begins in June and can go through to the end of September for late Maincrop potatoes.

The First Earlies can be ready just after they have flowered, it is worth checking on the size by carefully scrapping away the top surface of the soil to reveal the potatoes, which will indicate if they are the right size for lifting.

Second Earlies and Maincrop potatoes can be left in the ground until the foliage has died off, which would be around September. It is always worth completely cutting off any foliage 2 weeks prior to lifting, which ensures the potato skins toughen up and can be stored for the winter.

When lifting, it is important to use a good, strong fork and allow room so that you don't pierce the potatoes. Take your time and enjoy your find!

The First Earlies do not store very well and so it is best to eat these as soon as possible.
Second Earlies and Maincrop are ideal for storing, as long as they are in good condition, e.g. not suffering from any blight or pest damage. They should be stored in woven or paper sacks after they have been left to completely dry out in the sun for 2-3 hours, and a final check should be made to make sure there is no sign of any bad ones.

Furthermore, they should be stored in a frost-free place, such as a sheltered shed or garage, and should be checked once a week to make sure that there are not any bad ones in the sacks. If there are any that look diseased or soft, remove and destroy straight away, as even one can ruin an entire lot by spreading the disease on to the rest.

Growing Potatoes In Containers

You can also grow potatoes in containers. First Earlies do better than Second Earlies and Maincrops. It is important to make sure the pot is a minimum of 30 cm (12 in) across and deep enough for them to do their best.
There is such a variety of different pots available now,and if all else fails, you could always use your dustbin!.

Make sure that it has adequate drainage and put polystyrene or broken crock at the bottom of the container, and, if possible, raise the container off the floor by using bricks or pot feet.

Put a 10 cm (4 in) layer of compost (general multi-purpose) in the bottom of the pot and put 3 chitted, medium-sized tubers on the top of the compost. If your tubers are very large, you can cut them in half, making sure that each side has a good array of shoots.

Cover the potatoes with 15 cm (6 in) of compost and water in. The best position to keep them in is in a good, bright light, but sheltered.

When the shoots start to emerge, add approximately 10 cm (4 in) of compost and repeat the process until the container is full.

After the flowers have died off, it will be worth carefully scrapping away the top surface of the compost to see if the potatoes are the right size for eating.

The most important thing with containers is to make sure that they do not dry out, also give a liquid feed such as tomato fertilizer once a week, as per the instructions on the bottle.

Using the 'No Dig' Method

If you have an area which is very weedy, and you have no energy to clear it, there is a method which is now widely used called the 'No Dig Method'.
This involves cutting down to ground level all weeds and grass, then applying directly onto the soil either one barrow-load of manure per 10 m²(11 sq yd) or, if using compost, two barrow loads per 10 m². For a better guarantee of not going back to the weedy, grassy area, lay landscape fabric down before putting on the compost or manure.

Follow the normal way of planting, but instead of putting more soil on top of the seed potatoes, use straw or hay (only in sheltered areas where it is not likely to blow away). If this is not possible, use soil or compost.

To achieve the mound, it is best to keep putting compost, soil or straw on top of the shoots to achieve the 15 cm (6 in) mound sufficient enough to avoid the tubers from letting in light and turning green.

Harvest as described above.

Pests And Diseases - The Common Problems

Potato Blight (Phytopthora infestans) - This is the most common problem that potatoes encounter, and can severely damage tubers by rotting them off virtually over night.
It effects all of the potato family eg. Tomatoes, Solanum, etc....
It is a fungal disease which spreads through the air and develops in warm and humid conditions, causing the potatoes to develop dark patches on the skin of the tuber, and brownish spots on the foliage, which turn to yellow before causing the foliage to completely die off. Eventually, the potato will go rotten inside and turn into a smelly rotten mess.

Potato blight is usually killed off by cold weather, but that depends on the type of fungal spore, as some can survive.
There are chemical treatments which you could use but I wouldn't recommend them, as many contain copper, which isn't organically approved.
The best thing to do is to make sure that you dig all potatoes up each season and burn any diseased or dead affected foliage.
To help avoid blight, when watering, make sure that you water from the base rather than spraying directly onto the foliage, as this can cause the fungal spores to germinate, given the right humid conditions.

Blight-affected potatoes do not store well so must be eaten as soon as possible. You should always inspect any stored potatoes for signs of weak or diseased tubers which can effect the entire stored crop, remove any weak ones and destroy immediately.

Slugs are another problem with potatoes. They can nibble their way through the potato which leads to bigger holes in the centre, which will cause the tuber to turn brown and rot. It is more common in wet, heavy soils, and as the weather changes in September, a late harvest can reveal an entire crop to be damaged.

Common Scab - This mainly occurs during dry conditions and appears as a brown-coloured fungus on the tuber. However, it will not prevent the potato from being used as it is only on the surface, but is very unsightly. Water from the base during hot, dry conditions to help prevent scab from taking hold.

Blackleg - This affects the stem of the potato, causing it to go black and rot. It is more common in wet conditions and can cause the stem to decompose very quickly, gradually working its way down to the tubers.

Recommended Potato Varieties

First Earlies:

• Accent - A very early variety which is slug-resistant and crops well.
• Foremost - A very good flavour which cooks well.
• Maris Bard - This is ideal if we have a warm dry summer as it is drought resistance.
• Rocket - Crops well and is disease resistant.

Second Earlies:

• Kestrel - Slug resistant with an old-fashioned taste.
• Kondor - Resistant to potato blight and a heavy cropper.
• Nadine - A heavy cropper which can be used as a general purpose cooking potato.
• Wilja - Another good cropper with a general purpose cooking use.

Maincrop:

• Amour - Blight-resistant, does well in all soil types.
• Cara - Resistant to blight and drought, general purpose cooking potato with a heavy crop.
• Desiree - A red-skinned variety which tolerates a heavy soil. Good drought resistance.
• Sante - Large tubers with a good natural resistance to disease, likes all soils.
• Valor - Blight-resistant, with a good flavour.

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