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By Mrs Paterson, now Roger,
Potato Merchant, 38 Union Street, Dundee. [Premium—Five Sovereigns.]
What method of cultivation
ought to be adopted in order successfully to prevent a total failure of
the potato crop, and to produce a vigorous habit and constitution to
resist the attacks of disease to which the old varieties have been so long
subjected, is a question of vital importance to our country and to the
world, the potato being a necessary auxiliary of food, and consequently
the cultivation of it a great commercial enterprise. This question, for
many years past, has attracted the earnest attention of the statesman, the
philosopher, the economist, and the man of science, and now that disease
again threatens this palladium against famine (when this phrase was first
used, I question much if it was thought the object of the eulogy should
itself be the cause of famine and consternation), it must be obvious that
great necessity exists in agriculturists devoting their utmost thought,
care, and attention to the culture of new varieties of potato.
Potato disease is the
result of degeneration and decay, caused by repeated propagation from the
old varieties. As a natural consequence the plant must, and will wear out.
It becomes weak in constitution, worthless as a cropper, and subject to
many forms of disease from the vicissitudes of climate or atmospheric
action, not only after it has developed its stems, but before the germ has
risen out of the ground.
From the experience I have
had of potato raising and potato culture, my conviction is there is no
remedial cure for the disease, it being inherent in the plant, caused
partly by atmospheric action, the plant having the seeds of disease within
itself ready to be developed under favourable circumstances, and that the
present stock will be more or less subject to it.
The potato is only destined
to serve its day and generation the same as animal life, and a successive
and regular renewal of the esculent from the small seed found in the plum
of the potato, thus producing an infusion of new blood, is no doubt the
only effectual remedy for disease, restoring vigour and saving the plant
from annihilation. It was only about the year 1826 that disease in the
potato seems first to have attracted the attention of agriculturists. As
to the cause many conjectures were put forth, and all experiments tried
that human skill could devise to ward off the epidemic and regenerate the
old plant to its original strength, but in vain. Previous to the
visitation of the fatal blight of 1846, which in one night nearly
destroyed the whole crop of the nation, the potato had become so weakened
in constitution from repeated planting, that the plant had almost ceased
to flower, and the potato plum so entirely disappeared that I question
much if the rising generation were aware that ever the plum existed, or
that new varieties could be grown from them. Each plum has its small seeds
innumerable, every one of which produces potatoes of varied form, colour,
habit, and constitution, and wonderful to relate, perhaps none of them the
same as the mother plant, and great difficulty is experienced in getting
one good seedling out of the many varieties.
In the year 1853 the potato
in this country had ceased to flower or bear plums, which necessitated an
amalgamation of varieties blended together by atmospheric action and
insect labour, in order to produce plums.
Potatoes (Solanum tuberosum)
from Central America, Chili, East and West Indies, Australia, and Cape of
Good Hope, were imported into Scotland and planted promiscuously with the
"Rock" potato (brought into Scotland from Ireland in 1848), in a field of
newly taken in land where the atmosphere was damp, and the field
previously manured in the autumn with farm-yard dung. Most of these plants
produced flowers, but only a few bore plums, and still fewer plums
ripened. However, the experiment was successful; new seed was obtained,
and from these insignificant looking things have been produced the
countless new varieties that have restored the potato to the comparatively
healthy state it is now in from the dead rot of 1845, which threatened to
exterminate it from off the face of the earth.
I shall now explain how new
kinds may be raised from the small seed of the plum or apple of the
potato, to replace the old and worn-out varieties.
Gather potato apples when
ripe; those that fall off the shaws of their own accord are the ripest and
make the best seed. Store them in a water-tight vessel, and allow them to
remain there till the glutinous matter becomes decomposed, then bruise
them down amongst water, filter through a sieve so as to pass the seed
through, leaving the refuse back. Again mix the seed with plenty of clean
water, pass it into a sieve small enough in the meshes to retain the seed,
keep working the sieve well in the water till you are certain the seed is
entirely free from the pulp, then dry thoroughly on a thin cloth in the
sun, or indoors in a dry situation. It will then be fit for use. Sow in
March month in a box filled with properly prepared mould, covering the
seed about half-an-inch with the earth. The box may then be placed in a
greenhouse of moderate temperature, care being taken to keep the earth in
equal heat and moisture.
"When the plants are a few
inches above the ground, which should be in about a month, pick out the
most robust with plenty of earth attached, and transplant them to an early
border, which should slope to the south, manured, say with one-fourth
lime, one-fourth wood-ash, and one-half decayed leaf-mould, all mixed
together and scattered over the surface of the border. The lime will
prevent destruction by worms, woodash (the food of the plant), will
improve the skin and growth of the potato, and the leaf mould will serve
as a nutriment. The sets should be planted twelve inches apart so as not
to obstruct each other. Water a little when requisite. Hand weed. Draw the
earth carefully from time to time round the necks of the plants, taking
care not to chop, cut, or injure the stems, and continue their culture the
same as other potatoes. You will know when they are ready for lifting by
the leaves turning yellow and the decay of the shaws; they may then be
forked up and stored. Those that ripen by the middle of June should be put
away marked as earlies, and those about July as second earlies, and the
late ones as standard kinds.
It will be years of
continuous cultivation before you get quantity, or even some proof as to
quality, of any single variety, but just go on, carefully keeping every
kind separate. Discard all weak plants, and only grow those that appear to
be compact in growth, well formed in the tuber and vigorous in habit.
Carefully store the produce of each plant in a box by itself.
In March replant, during a
moist day, each variety in a drill by itself in an open field of easy
soil, and in a well sheltered situation having a southern aspect, properly
ploughed and manured the previous autumn with about twenty tons of
farmyard manure to the acre. Open furrows three feet apart, and plant
sixteen inches from set to set. Plant carefully, not to injure the
sprouts, placing the sets with the eyes uppermost. Potatoes that have not
sprouted but merely pushed out buds are the best, but if the sprouts are
long they should be removed, as it would be difficult, unless in garden
planting, to keep them entire. The setters, who should move in a
retrograde position, should be provided with baskets from which to drop
the sets into the drills. Make it a strict rule to cover up each drill as
soon as planted, in the manner in which they were before opened, and at no
time lay down more sets than can be covered up immediately; for if left
exposed to frost they will be useless, or if left to the action of the sun
and then covered up with the hot earth some of their vitality maybe
destroyed, and you will not get a regular braird. If a top-dressing of
wood-ash or charred vegetable mould is thrown over the drills before the
last furrowing up, it will be serviceable as extra manure. Two
hundredweight of guano to the acre makes a good azote. On stiff and
retentive soils, decayed tan, if freely used, has been proved to be highly
beneficial in warding off blight. When the haulm appears above the ground,
which if the weather is favourable will be in about a month, the hand hoe
or scraper should be passed between the drills so as to destroy all weeds,
which are very injurious to the growth of the potato. By the time the
plants are meeting in the drills they should have had their last furrowing
up.
"If the blossoms of the
potato plant are picked off before they run into plums (which could be
done by boys), it will increase the weight of the tubers considerably, as
much strength of the plant goes to nourish the plums." When potatoes are
ripe the sooner they are lifted the better, dry weather being chosen for
the operation. All should be lifted and stored by the end of October, or
before the frost can injure them. There are various ways of taking them
out of the ground, the hand grape, the plough, single and double, and also
machinery, but whatever method is used, the principal object should be, to
lift them all, and to gather up all as you proceed, for if once trod into
the soft earth no harrow will take them out. The intrinsic value of the
potato consists in its being neither too large nor too small, rough
skinned, white fleshed, fine flavoured, mealy, and the eyes few and
shallow.
After the trouble of
raising and cultivating such a precarious and valuable crop as the potato,
great care should be taken in the storing. The best method to keep them is
in clamps or pits, either round or prismatical in form, and should slope
evenly from the roof to allow the rain to run off easily. The pit should
be laid with the ends north and south to keep off as much as possible the
frosty winds of winter. The bottom should be four or five inches below the
level of the ground and three feet six inches wide. The height of the pit
from three to four feet. The lighter and thinner potatoes are pitted the
better. No matter how long the pit is, supposing there is room and plenty
of wheat straw to cover it. The most important thing to guard against is
heat, and that especially in new seedlings, as they are young and vigorous
and full of moisture when taken out of the ground. Place plenty of clean
dry straw on your potatoes, say about a foot thick from top to bottom.
Then cover very lightly with earth, just sufficient to keep the straw
down. On no account, if you value your potatoes, cover completely with
earth till they have had time to cool. In about a month or six weeks, if
there is danger from frost, place sufficient earth on the pit to secure
the potatoes for the winter. If plenty of straw is used it will be
sufficient to keep out any frost till the potatoes have had time to throw
off their moisture which they will readily do. All the shaws should he
gathered off the field in a heap. I have often kept a pit all the winter,
especially the Bovinia potato. with but a light covering of earth loosely
thrown on, and the old potato shaws thrown thickly over the top. Frost and
snow never hurt them, and they came out in March, cool, hard, and sound,
and what is of great importance, had a splendid flavour always essential
to a good table potato. One reason why we often get potatoes of doubtful
quality is through careless storing, and not the fault of the ground they
are grown in or the seed planted. Further, to protect the plant, potatoes
for seed purposes should be grown especially for that end and not for an
abundance of crop, and in a different district altogether from where they
are required for planting for ware purposes. Put them as far north as
possible, to make them hardy, and if possible on newly taken in land of a
light loamy nature or a clean sandy soil by the seaside.
The seed should be planted
in March, the sets 12 inches apart and 2½ feet between the drills. This
will give a uniform size, and nearly all of them will be fit to plant
whole, and will contain more soluble than starchy matter. In many cases
such seed when planted in good soil will yield several tons more per acre
than what is called "middlings," such being the after-growth of the plant
and unfit for seed purposes. Depend upon it, it is folly and mistaken
economy to use such seed. They will not produce uniform crops, and they
are not sure to produce even an average one, and the tubers not up to
size. When disease appears it is first seen in such crops—and no wonder;
for the seed perhaps is grown for years in the immediate neighbourhood, or
the small potatoes, the refuse of those sold in our markets for domestic
purposes, dressed over a 1¼ in. riddle for seed; such potatoes are too
weak in constitution to bear a crop, let alone resist disease. In fact if
you wish for crops of good quality, regular in the braird, strong in
growth, and with abundance of tubers, you must select your seed grown for
that purpose.
Potatoes grown in the
manner I have described for seed, do not approach in quality or shape
those grown for table use, the exposed situation they are grown in not
admitting of either; but when removed to a more genial climate, they are
often so much altered for the better that you would scarcely believe they
were the same kind. In all cases care should be taken to select seed
suited to the soil you intend to plant in. Rocks, regents, and kidney
potatoes put out long filaments and throw their tubers wide of the shaw,
so that it is injurious to plant these varieties in a strong soil, which
naturally hinders their growth, when a light sandy soil would encourage
that particularity and give them free scope. Other kinds, the Victoria for
instance, press the tubers so closely together that the soil in this
respect is not of so much consequence; yet strong soils, as a rule, do not
give potatoes of fine quality or the best adapted for table use.
Material good has been
produced in keeping away disease, by transferring seed from one locality
to another. Remove from an unproductive to a more generative soil, and
from a cold to a more genial climate, if you wish to propagate largely. If
whole sets are available they are the surest and best for planting. They
should weigh 2 or 3 ounces each. If cut seed is used the number of sets
must depend on the size of the tuber and the number of eyes they possess.
Kidneys and flukes are best planted whole, as they have few eyes and only
at the rose end. Victoria may be cut into two sets straight down the
centre. Regents, rocks, early round, and bovinia in angles, ranging in
size and number according to the eyes of each tuber. When seed potatoes
are fresh and in good order, they cut crisp and exude a good deal of
moisture, which soon evaporates. The ground should be ready to receive
them when cut, and it is not good to heap them up in a cart, shed, or barn
when cut. I believe most positive injury is done to the crop by such
treatment, as fermentation will set in and destroy life. The surest and
best method is to cut and plant immediately. It will take 12 or 15 cwt. of
potatoes to plant an acre.
In regard to varieties,
they are at present so numerous that a list is of little use, as the
application would depend on the soil and climate. There is no difficulty
in selecting for field or garden planting, potatoes which have at least
undergone a partial test, conducted with great care, and reported upon
from time to time by professional and amateur growers. This enables others
to select seed best suited to different localities. No absolute rule can
be laid down as to when particular kinds may be planted, but they may be
classed in three divisions. Plant early kidneys in February, second
earlies in March, and late varieties on to May. Bovinia, being of quick
growth, may be planted as late as June.
Although I have compiled
these remarks from my own experience, and not gathered them from books, I
do not presume to uphold them as a complete guide to agriculturists, but
rather in the hope that they will add one link to agricultural knowledge
and domestic economy.
Before concluding, I would
ask agriculturists of experience what the consequence would be if blight
in the potato plant again swept the land as in 1845-46?
Though the new seedlings
that have been raised have not been exempt from disease, there is no
evidence to show that the apples gathered for the purpose of raising the
new stock were the product of sound plants. Quite the opposite. If the
argument holds good that the seeds of disease are in the plant ready to be
developed, Are the plums free from disease? I say no; but if the process
of cultivating new kinds is carried out, it must, and will, result in the
production of fresh and strong stock.
I suppose that every person
is aware that light soils produce better-flavoured potatoes than those
grown on clayey soils; for the soil has an influence whatever may be the
variety, and those grown on land previously manured in the autumn are
finer flavoured than those planted in immediate contact with the dung in
the drills.
Manuring in the autumn is
one of the best methods to adopt, with a top-dressing of wood ash, or
ashes from pairing and burning; they supply a valuable potash, the food of
the plant.
The Americans burn
quantities of timber for black ash and potash, and which forms a very
valuable article of commerce. Seaweed is also freely used where it can be
had.
As potato possesses a
spreading root, it requires a uniform manuring, not an instantaneous
supply of soluble matter. The esculent being produced and perfected during
the latter period of the growth of the plant, it wants the greatest amount
of nourishment at that time for the development of the tubers.
What invigorating
substance, and in what quantity it should be used, is a most difficult
question to answer, particularly as manure in all cases acts more quickly
on plants when it is well prepared.
In an economical point of
view the safest and best manure for potato is that which contains plenty
of azote, and does not decompose too quickly. The following will be found
to be a good mixture for potato manure:—4 cwt. of mineral superphosphate,
2 cwt. of muriate of potash, and 2 cwt. of sulphate of ammonia per statute
acre. This is suitable for light soils. In the case of heavy soils, 2 cwt.
of nitrate of soda takes the place of the same quantity of sulphate of
ammonia. These manures are mixed with twice their weight of
finely-screened earth, and sown broadcast before planting the potatoes.
The above will give fully as good returns as 20 tons of farm-yard manure.
Had farm-yard manure been
other than a compound containing all the ingredients of the produce raised
on the farm, many more potato failures might have occurred. These
ingredients undergo various chemical changes while circulating, and are
prepared and fitted for entering when and where it is necessary into the
solid and fixed parts of the potato plant, and each exercise a chemical
action on the elementary bodies, which they meet with in the stems and
wood of the plant. Ammonia and ammoniacal salts, as a rule, produce bulk;
and phosphate also produces quantity and bulk. The aim should be to secure
both.
If agriculturists wish to
cultivate their soils successfully, they must spend a deal of money on
manures, as the present state of cultivation necessitates the application
to the soil of more fertilising agents than is obtained from farm-yard
manure. Potash is an indispensable article for invigorating the health of
leguminous plants, and where alkali is abstracted it must be applied with
no sparing hand.
However easy it may appear
to apply artificial manures to the soil, as long as the knowledge of
chemistry is so limited in the respect of application, manures must
continue to be applied much in the same manner as at present, with such
gradual improvements as inquiry and progressive chemical knowledge may
direct. Has the agriculturist nothing to answer for? Does he restore to
the ground, by manure, those properties which former crops have taken
away, and which are necessary for the healthy cultivation of potato?
Last century Sir H. Davy
called the attention of agriculturists to the fact that the land became
exhausted from repeated cropping, and that something ought to be done in
partial appliance of chemicals. About 30 years ago Professor Liebig
directed attention to artificial manures with a view of replacing the
azote that had been extracted from the land. I do not mean to infer that
the improper use of artificial manures has been the cause of potato
disease, but this I know, that land never before cultivated is most
productive of potatoes free of disease. |
