October 3, 1SS9. ] 
JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 
281 
1 | 
NOTES ON SOILS. ■ 
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AITE are told by vegetable physiologists that primitive soils or 
V V pure earths are of no other use or benefit to plants than merely 
affording them a medium by which they fix themselves in the most 
favourable position with regard to their future growth. Luckily the 
horticulturist has little to do with pure earth, it is only when soil 
is more or less charged with organic matter that it is in any way 
fit for his purpose, and in proportion to the presence or absence of 
this matter is the value of the soil to be estimated, superabundance 
•or deficiency to be corrected. Various are the operations for im¬ 
proving soils independent of manures ; and it is a more serious 
•consideration to the gardener than to the farmer. For instance 
'vegetables grown in the fields where the land is less glutted with 
manures are to be preferred to those grown in highly manured 
gardens. Hence the necessity of improving the soil by other ways 
than gorging it with more manure than is necessary for bringing to 
.perfection such vegetables as are expected to be produced. 
The first method of improving soils is by pulverisation, which 
operation is performed by trenching, digging, and ridging, the main 
object being to give scope for the roots of vegetables to strike out 
in every direction in search of nourishment, and also to promote 
•the free circulation of air and water. Light soils in the course of 
time, if left undisturbed, become too compact for the free growth 
•of the fibrous roots of plants, as well as for the proper admission 
of air, and water, and heat ; while the strong lands, on the other 
hand, in a shorter time become impenetrable by the roots of 
vegetables. No vegetable flourishes without an abundance of roots. 
Therefore the soil should be adapted as much as possible to the 
•encouragement of these necessary organs, as we are convinced that 
the quantity of nourishment taken up depends more on the number 
of absorbing fibres than the quantity of nutritious matter contained 
in the soil. 
Digging between the rows of some plants is a matter of great 
importance to them, operating on the principle of pruning, cutting, 
and shortening the extending fibres, causing them to throw out a 
number of others, the plants being thus enabled to collect a larger 
quantity of food. It is necessary before planting or sowing that 
the soil be reduced to a proper consistency, and also to preserve it 
in that state during the growth of the plants by repeated digging or 
hoeings between the rows. Capillary attraction, which renders the 
moisture of the soil more uniform, is also promoted by digging, &c. 
It is very evident that those soils where the particles are the finest, 
such as sand, or reduced by repeated diggings or trenchings, are 
the driest. 
Gravels and sands that are naturally reduced to fine portions 
scarcely retain any water, and often not sufficient for the growth of 
vegetables, which accounts for their unfruitfulness, while clays, if 
not acted on artificially, either do not absorb the water, or when 
they do, retain too much. It is very essential that the soil should 
be brought into a condition to retain a certain quantity of water 
and no more, as without this all endeavours to assist by means of 
manures will be useless. 
The depth of pulverisation depends upon the nature of the 
soil and subsoil. In strong clayey soils it can scarcely be too deep, 
and even in sandy soils, provided the subsoil does not contain any¬ 
thing hurtful to vegetables, the admission of air is very important. 
It is also necessary that all soils should be kept open as much as 
No. 481. —Vol. XIX., Third Series. 
possible for the admission of a sufficient quantity of heat to the 
roots of plants. Earths are bad conductors, and it would take a 
long time before the heat could penetrate to a certain depth, espe¬ 
cially in spring, to be of any i mportance to roots of vegetables, unless 
by frequent turnings the soil is capable of admitting a free entrance 
of the sun's rays as well as tepid rains. It is also necessary that 
soils should be open for effecting those changes all manures have 
to undergo before they can be fit food for vegetables. Animal and 
vegetable substances undergo decomposition when exposed to the 
action of air, light, and water. Improving soils by pulverisation is 
very important ; but still we must not think that is all, for in the 
strictest sense of the word it only benefits the plants by increasing 
their fibrous roots. Garden ground should never lie uncultivated 
for any length of time unless sown with grass. The aeration of 
lands in winter is also very important, and the water in the soil 
freezes, causing it to crumble down into a fine mould. Insects and 
their eggs, with the roots of weeds, are also destroyed in larger 
quantities than may be supposed. 
The tenacity of clayey soils may be corrected by sand, lime, 
chalk, or coal ashes. Such soils cannot be too much worked ; 
every opportunity should be taken to rough dig and ridge them ; 
taking care such operations are not done when the soil has been 
saturated with wet. Soils which contain a large quantity of gravel 
are not quickly or readily enriched by manures, the finer portions 
being washed out by rain, and not being capable of retaining a 
sufficient quantity of moisture suffer greatly from drought in 
summer ; but if they are cleared of a portion of the small stones 
and some strong loam added to form a body, they will be found 
capable of keeping enough moisture for the growth of future crops. 
Light soils, however, have their advantages, for from these we 
obtain our early spring crops, as they are much more capable of re¬ 
sisting frosts than stroDg soils. Being warmer they afford less 
moisture, and the crops do not grow so luxuriantly, and are there¬ 
fore much earlier ; but when summer comes they are either 
unproductive, of short duration, or fail altogether. 
The beau ideal of a fertile soil, it is remarked by the late 
Mr. G. W. Johnson in “Chemistry of the World,” is one 
which contains such a proportion of decomposing matter as to 
keep the crop growing there always supplied with it in a fit state 
for absorption, yet not so superabundantly as to render it too 
luxuriant, if the object in view be the production of seed ; but for 
the production of those plants of which the foliage is the part in 
request, such as Spinach, or of edible bulbous roots, such as 
Onions, which have a small expanse of leaves, so as to be almost 
entirely dependent upon the soil for nourishment, there can scarcely 
be an excess of decomposed matter presented to their roots. 
Asparagus especially demands abundant nourishment, as, similar to 
the Onion, it has little foliage and fibrous roots. 
But it is evident that to insure these desiderata in any soil and 
at all seasons is impossible, as a soil that would do in one climate 
would fail in another if the mean annual temperatures should differ, 
as well as the amount of rainfall during the same period. In the 
west of England we have twice as much rain as in the eastern 
counties, hence a soil in the east may be more tenacious and richer 
than the one required for the same crop in the west. 
Respecting affording warmth to plants Mr. Johnson says, “ The 
earth is of considerable importance, and the power of accumulating 
and retaining it varies as much in soils as the proportion of their 
constituents.” Sir H. Davy found that a rich black mould, contain¬ 
ing one-fourth of vegetable matter, increased its temperature in an 
hour from 65° to 88° by exposure to the sunshine, while a chalk 
soil registered only 69° under similar circumstances, but the first 
when removed into the shade cooled in half an hour lo°, whilst the 
latter only lost 4°. This explanation will show why crops on light- 
coloured tenacious soils are in general so backward in spring, but 
retain their verdure longer in autumn than those on black light 
soils ; the latter acquire warmth more readily, and part with it with 
No. 2140.— Yol. LXXXL, Old Series. 
