Growing Potato

A native of South America, the tubers are believed to have first reached Europe from Peru. Today, the potato is the staple diet in many countries round the world but nowhere does it grow better than in the cool, moist climate of Britain where more than ten million tons are produced each year.

Apart from its food value, the potato possesses another important quality. That is its ability to crop well in ‘dirty’ land provided it is well manured. This is land which has become infested with perennial weeds which are of 1 en difficult to eradicate. Due to the process of lifting and general cultivations, the soil is thoroughly cleaned and after manuring, it will be in perfect condition for the planting of other vegetables the following year. Again, land of a peaty nature, of 1 en low lying and which would grow few other crops apart from strawberries will. if well manured, grow good potatoes which prefer an acid soil. For this reason, soil well limed or of a calcareous nature will produce a crop liable to scab and one much reduced in weight.

A heavy soil, which in a summer of high rainfall will remain wet and cold, may cause the tubers to decay from fungoid diseases so that a clay soil should be brought into condition by incorporating quantities of garden compost or decayed strawy manure.

Peat, leaf mould and wood bark are also valuable to lighten the soil and will also help to retain if dug into a light, sandy soil.

The ground should be made ready during the early winter wraiths, leaving the top soil in a rough condition, to be pulverised by frost and wind during winter.

Starting the timbers The yield of a crop will be much increased if the tubers are sprouted before planting whilst this will ensure the earliest possible crop depending upon soil and situation. With early potatoes, a crop at least 3 weeks earlier than with unsprouted tubers may be expected, whilst with the maincrop a 20 per cent heavier crop may be obtained, due to the longer growing period. The tubers should be clean and even in size.

A frost-proof room is essential for the sprouting but first obtain the tubers or ‘seed potatoes’, as tubers produced for replanting and grown on maiden land are called, from a reliable grower. They should be ‘certified’ as having been grown in Scotland or Ireland or on one of the islands situated in the more remote parts of northern Britain. Potatoes grown for seed on high ground in the north of England will be almost as good, being clean and possessing exceptional cropping vigour.

A method of sprouting is to place the tubers, `rose’ end upwards close together but not quite touching, in peat t inch deep in a shallow wooden box. ‘The tubers should not be cut. The ‘rose’ end is usually the wide end containing the greatest number of eyes. Place the boxes in a light airy room but not in sunlight whilst frost must be excluded. The Fenland growers stack the boxes in specially constructed sprouting houses.

When to begin the sprouting will depend upon planting time. The earliest plantings are made in Cornwall and Pembrokeshire where spring frosts are almost unknown and where early potatoes are planted in February. They are put down for sprouting about Christmas time. In other parts of southwest England and Scotland, the early crop is planted in March ; elsewhere, mid-April is a suitable time and as the earlics are more tender, it is usual to plant ‘late’ potatoes (the maincrop) early, and early potatoes late’. Sprouting should commence about 6 weeks prior to planting time but this will depend upon where the sprouting is to take place and the amount of warmth given. Short sturdy sprouts are required, not more than t inch long, otherwise they will break off when planted. Where there are more than two sprouts, the two strongest are retained and all others rubbed out. Do not plant too early, wait until the soil is in a friable condition and has begun to warm. This may not be until early May in the north especially if the soil is heavy.

For a heavy crop, take out a trench to a depth of 9 inches and make the trenches 2 feet apart to allow for ‘earthing’. At the bottom place 3 inches of decayed manure or material from the compost heap and over this, 3 inches of peat. Into the peat, the tubers are carefully pressed 2 feet apart, the sprouts (or eyes if not sprouted) about 4 inches below the top of the trench. Befbre covering them with soil, place more peat around the tubers or use soil which has been passed through a fine riddle.

To the soil to be used to fill up the trench, give a 2 ounce per square yard dressing of superphosphate ollime and sulphate of potash mixed together. This will increase the yield, encourage earlier maturity and help the plants to resist disease. The mixture should be in the proportion of 2 parts superphosphate to I part potash. Nitrogenous fertilisers should not be used for they tend to make for excessive top growth and a ‘sof 1 ‘ tuber, liable to attack by disease whilst they become dark after cooking.

On low-lying land of a heavy nature, the tubers should be planted on ridges, in V-fashion, At the top of the ridge a drill 6 inches deep is made and lined with peat. Into this the tubers are pressed and the drill filled in with finely riddled soil containing the superphosphate and potash. Never plant potatoes too close together or the haulm (the leaves and stems) will grow weak and be prone to disease. Weak haulm will mean a greatly reduced crop.

It is important to plant potatoes in an open, sunny position so that the plants may obtain the maximum of sunshine. Make the rows from north to south, to allow both sides of the rows to receive the same amount of sunlight. If possible, early potatoes should be given a southerly slope and as light a soil as possible: this will ensure that maturity will be two weeks earlier than where growing in a less favourable situation.

For an early crop in the more exposed gardens, an early variety may be planted in a frame over a mild hot bed. A 6-inch depth of compost is placed in the frame and on top is placed a 6-inch depth of riddled soil into which the tubers are planted with a trowel, spacing them 9 inches apart and just covering them with soil. Water in and cover with lights. Should there be frost about, cover the lights with sacking at night and remove by day. If the tubers are planted about mid-March, they will yield a useful crop of ‘new’ potatoes at the end of May. If the haulm is earthed up with a peat and soil mixture this will help to prevent loss of moisture about the tubers as the days become warmer.

As the foliage appears above the soil, it should he earthed up about 3 inches and again a month later to a similar depth. This will prevent the foliage from being damaged during cultivations. At the same time and as a precaution against ‘Blight’, spray the foliage with BordeauR_Mixture.

A reliable indication as to when the crop is ready to lift is when the foliage begins to die down, though for show or where the crop is required to eat at home, lifting of the early varieties may commence in June, and the mainerop towards the end of August. If carlies, second earlier and maincrop varieties have been planted, there will be tubers to harvest from June until October when the winter supply will be available from storage. Potato

Lift the tubers with a fork, taking care to place it well away from the plant for the tubers spread out and are easily damaged by careless lifting. Where lifting for exhibition, it is better to do so with the hands, selecting a day when the soil is dry and friable. Scrape away the soil and lift the tubers one at a time placing them, after shaking away the soil, into a bucket lined

with a clean sack which is then used to cover the tubers to exclude light. Potatoes lifted early for use or for exhibition should be kept under the stairs or in a cellar, away from light otherwise they will turn green.

‘New’ potatoes may be enjoyed all the year round if a quantity are placed in a metal biscuit tin filled with dry peat and buried 12 niches deep in the garden, a stone marking the position.

After lifting, burn the haulm so as not to perpetuate disease which would contaminate the garden compost heap.

Exhibiting The potato is one of the most inter- esting, of all vegetables on the show bench for it is obtainable in many sizes, shapes and colours and never ceases to entertain. The tubers are lifted about mid-August whilst the soil is still friable and readily falls from them. They should not be washed but on show day may be wiped with a damp cloth, taking care not to damage the skin. The tubers must be dry when placed in tissue paper and packed in cotton wool in a box or basket. They should have been selected for uniformity, each being free from marks or slug damage and showing no traces of `greening’. Usually six tubers of a single variety are arranged around a dish. They must be neither too large nor too small and should have few eyes which should be shallow. 4 points are awarded for condition; 4 for size; 4 for shape; 4 for eyes; and 4 for uniformity.

Four different types or classes are provided for

(a) Kidney-shaped—white

(b) Kidney-shaped —coloured

(c) White rounds

(d) Coloured rounds

Outstanding exhibition varieties are ‘Craig’s Royal’ (d); `Pentland Cream’ (b); ‘Arran Comrade’ (d); ‘Catriona’ (b); `Dr. McIntosh’ (b); `The Bishop’ (a); ‘Angus Beauty’ (b); ‘Dunbar Standard’ (a); `Arran Victory’ (d).

Pests and Diseases

BLACK LEG

Bacterial rot of potato tubers may be troublesome in a wet season. The disease starts at the end of a tuber causing shiny areas and when cut, emits an unpleasant smell. Clean seed will do much to prevent an outbreak whilst it is preferable to plant whole tubers rather than cut portions containing an eye.

BLIGHT

Dangerous if it takes hold but is easily prevented by spraying the foliage in early July and again a month later with Bordeaux Mixture. The Blight attacks the leaves as brown spots; later the whole plant turns brown whilst the tubers are also damaged, sunken areas appearing on the surface.

COLORADO BEETLE

Rare in Britain, it is so destructive to pbtatoes that it is a ‘notifiable’ pest. It has orange and black stiped wings and when tally grown measures half an inch long. It winters in the soil and lay its orange eggs on the plants. The grubs are also orange and where in numbers will quickly wipe out a plantation. As a precaution. treat the soil with Aldrin dust before planting.

EELWORM

This pest attacks the tubers causing them to become a slimy mass whilst the foliage turns yellow and dies back..I.here is no known cure and badly infested land should be rested frbin potatoes for f’our years. Where they have caused only limited trouble, treat the soil with Jeyes Fluid at a strength of 2 tablespoons tot gallon of water a month before planting.

LEAF SCORCH DOC

to potash deficiency, the leaves curling at the margins. Later, bronze and yellow blotches appear. A light application of sulphate of potash at planting time will prevent an outbreak. SCAB This attacks the tubers in the form of rough, scab-like spots and, where the infestation is severe, the scabs may cover the whole surface. It is prevalent only on land of a calcareous nature or where heavily limed for a previous crop. Green manuring before planting potatoes, by sowing and digging in rape when 2 inches high will do much to prevent an outbreak.

WART DISEASE

A ‘notifiable’ diseaseand on infected land only wart-immune varieties such as ‘Arran Pilot’ (early) and ‘Dr. McIntosh’ (niaincrop) should be grown. It first attacks the stems and lower leaves but it is usually found only on the tubers which upon lifting may have the appearance of cauliflower-like structures. Many will break off in the soil where they remain to contaminate the following potato crop. Clean seed will go far in contributing to immunity but by EEC (Common market) decree all varieties susceptible to wart must be eliminated. Those listed here are immune.