WHAT IS SOIL?
When preparing garden soil, it is essential that you determine which type of soild you have in your garden or plot. Soil is the term we use to describe the surface layer of the earth’s crust. Briefly there are two types of soil :-
(a) Soil that has been under cultivation tor a year or more, that is, under the plough, or kept open by hand digging.
(b) Soil that has been under grass, in meadow or pasture, or laid down as a lawn.
As gardeners we are not concerned with the unbroken rocks that protrude from the soil in various parts, except when we use them for ornamental purpors, as for instance when we make rock gardens and paths. These rocks are the basis of the various soils, the soils themselves being the rocks crushed or broken by weather action and by the growth of vegetation through the ages. Naturally, as the rocks vary from district to district, so also do the soils of different localities vary, but for the gardener the golden rule is that “ There is no bad soil.” Every variety of soil has some virtue, and every variety of soil can be so prepared that it will yield good crops. Naturally the soil varies in the amount of hard Work needed to bring it into good condition, but there may be some consolation to those who find thd task difficult in the fact that the difficult soil is sometimes more fertile than easy soil when it is once in “good heart.”
TYPES OF SOIL
Beginners often ask “ What is light soil ? “ The answer is that “ light” means light in weight on the spade, not light in colour. The difference between light and heavy soils is due to the size of the soil particles of which they are composed. Heavy soils are composed of very fine particles, which pack closely’ together. They also hold moisture readily, and very quickly become caked and sticky, or when dried out set into a cement-like lump. Light soils are composed of large soil particles, sand chiefly, and these do not readily adhere to each other, so that when you tread over light soil it shifts under the foot. Light soils also allow water to pass very readily through them, and so become dry rather rapidly in periods of drought.
The difference between these two extremes is soon discovered by the cultivator, and he must adapt his soil treatment accordingly. Light soils, ,which quickly lose their moisture, need very heavy dressings of heavy, sticky manure —cow or pig manure is ideal—leaves, and other moisture-holding materials. In addition, any artificial fertilizers that are applied should be given in spring or during the , active growing season of summer. If they are given in autumn they will probably disappear through the soil and be below the part reached by plant roots when they are required.
Heavy soils; on the other hand, need gritty matter, sand, strawy manure—horse manure if possible—and any other materials that will keep the texture of the soil more open. Artificial fertilizers are often applied in autumn in order that they can work. On the soil itself during winter, breaking down the lumps, and gradually penetrating the top spit.
Some soils are very chalky ; they may perhaps lie over chalk deposits, which are near enough to the surface to be brought up during digging. These are called calcareous or chalky soils, and their treatment is a little different from soils which are deficient in lime. Some soils are composed chiefly of decomposing plant fibres, and free from any trace of lime. Such soils are slightly acid, and although they are ideal for the cultivation of certain flowering plants, they are only a good home for food crops after they have been well limed to counteract the acidity. These soils are generally known as peaty soils. The finest potato growing soils of Lancashire are on the sites of old peat beds.
Old woodland soils, where many seasons’ fall of leaves constitute the top layer, will also have this slight acidity which must be counteracted by additions of lime, but woodland soils are, when first cultivated, rather richer in plant food (and in pests) than peaty moors.
What may be regarded as ideal soils are the marly soils found in many parts of the country, which are very fertile and contain a proportion of lime, and also the cultivated “medium loam” that gardeners produce by deep digging and adequate manuring of any other soil type.
No matter what type of soil the garden has there are sure to be some disadvantages, so adopt methods to improve the soil and where possible, cultivate the plants most suited to the conditions.
TESTING A SITE
There are three things that I do on visiting the site for a new garden : first I dig a few trial holes about a foot square and a in. deep in half a dozen places. This enables me to inspect the nature of the soil. Secondly, I note the kind of vegetation growing on the plot as this is also a guide to the type of soil ; for instance, corn spurrey is indicative of a poor soil , rushes of a sour, marshy soil ; and rich, luscious grass shows a fertile soil. Thirdly, I note the amount of sunshine and the aspect of the plot.
Recently I opened a trench on a new – site to connect a water point. The trench was about 3 ft. deep and I noticed that water accumulated at the lower end revealing a hidden spring. Unexpected discoveries such as this are best exposed right at the start so that full use can be made of them or the necessary: steps taken.
If the soil is waterlogged, holes dug here and there will quickly fill with water and from this can easily be seen the amount of drainage required. Trees often occur on a garden site and these should never be destroyed without careful consideration. Sometimes there are far too many trees which must be considerably thinned out, but one or two should always be preserved as they can, with care, be introduced into the layout scheme with delightful effect.
The most fertile soil is in the top layer, but to improve drainage and fertility it is necessary. To break up the subsoil. This is done by double digging or standard trenching. The soil is moved from the first trench and left in a heap for filling in the last trench when the digging is completed. The subsoil is–broken up with a stout digging fork but left where it is, and into it is Worked manure, stones if they are not too large, grass clippings and vegetable matter.
Ridging is carried out in three operations. Mark the ground to be dug in strips three spades wide, A, B and C. Start at the far end of the first and take out a trench I ft. wide. Then turn spit A into the centre of the trench, followed by spit B also into the centre and finally spit C on top of the first two. When the whole is completed there will be a series of ridges parallel to each other. This method of ridging is especially beneficial for heavy clay soils.
USEFUL TOOLS FOR PREPARING GARDEN SOIL
I. Border spade.
2. Digging spade.
3. Border fork.
4. Digging fork for heavy soil.
5. Digging fork for ordinary soil.
6. Iron rake.
7. Edging iron.
8. Draw hoe.
9. Dutch hoe.
10. Five-pronged cultivator.
II. Universal hoe.