General Soil Operations
Man depends on thefor his living. It is therefore important to know how to cultivate it properly. But there is no value in cultivating land just for the sake of carrying out the operation, for every time the land is worked some humus is lost. Cultivation should, therefore, be carried out with restraint.
It is not advisable to dig soil deeply or, in the summer, even to dig it at all. Nature’s plan is to build up humus from above year by year. Therefore the work in the spring and summer should consist of light hoeing only, except where it is necessary to prepare a piece of ground for another crop, when a light forking may be needed followed by a light treading and a light raking.
Single digging consists of turning over the soil to a depth of about 10 in., and during this process anythat are growing on the surface should be buried.
When digging a plot, first take out a trench at one end of the plot roughly a spade’s width and a spade’s depth. Put the soil from this trench in a heap at the other end of the plot, so that when the plot has been dug the soil from the first trench can be used to fill in the last trench.
Then, alongside the first trench, mark out, preferably with a line, another strip a spade’s width across, and gradually dig the soil over to fill the first trench and to form a new trench of the same width. This is done by first plunging the spade at right angles to the first trench, and then plunging it parallel to the trench so that a rough square chunk of soil the width of the spade is cut out. It is then simple to lift the chunk of soil, invert it and throw it forward into the trench alongside. If desired, put some well-rottedor old manure at the bottom of the trench before the soil is thrown in. Apply it at the rate of a bucketful to a yard-run of trench.
DOUBLE DIGGING OR BASTARD TRENCHING
In double digging, as the name implies, the soil is dug to a depth of two spits. The soil is always left in its original layers: the top spit remains at the top and the second spit remains underneath.
Double digging is sometimes called bastard trenching, and two methods are in use; the first is for cultivated ground and the second for grass land that has not been cultivated before.
Mark with a line and dig out a trench 2 ft. wide and a spade deep at one end of the plot and put the soil from this trench in a heap at the other end of the plot. Next fork over the bottom of the trench well, and if any manure is to be added put it on to the forked soil. Move the line back2 ft. to mark out another trench. Dig over the soil from this trench into the first trench, taking care to keep the soil level and the trench at an even depth, and to scoop up from the bottom any loose crumbs of soil, which should be put on top of the soil in the first trench. Now fork over the bottom of the second trench well, adding manure if required, and then turn into it the soil from a third trench. Repeat this process until the entire plot has been trenched, putting the soil from the first trench on top of the forked soil in the last trench. If the soil is heavy, do the work in the autumn, and leave the clods rough as they fall, making no attempt to fork them down. This rough cloddy land exposes the greatest surface to the frosts and cold winds and ensures an easy-to-work soil the following spring.
Mark off a trench 2 ft. wide, skim off the turf and dig out the trench to a spade’s depth at one end of the plot. Carry the grass sods and soil to the other end of the plot, making two separate heaps. Then fork over the soil at the bottom of the trench. Next, move the line back 2 ft. and skim off the turf from this 2 ft. strip, placing it grass side downward on the forked-over base of the first trench. Then cut up the turf with the spade into pieces roughly 3 in. across. Do not put any compost or manure into the bottom of the trench, as the grass will supply the necessary. To help the grass sods to rot down properly, cover them with a fish fertilizer containing 6 per cent potash.
Next, dig out the soil of the skimmed strip to a spade’s depth, and put it over the cutup turf in the first trench, then follow by forking over the soil at the bottom of the second trench. Take care to keep the sides of the trenches vertical. Continue in this manner and finish by-putting the turf and soil from the first trench into the last trench.
Ridging or ridge trenching is very useful on heavy soil. The work is carried out in the autumn with the idea of presenting the greatest possible surface of soil to the action of the winter weather. The channels in between the ridges help to remove excess moisture from the soil, so that ridged land is usually easily workable after one or two dry days in spring.
Dig out a trench 2 ft. wide and a spade’s depth at one end of the plot, as if bastard trenching. This trench should run the whole length of the plot and preferably down the slope of the land. If the land is level the trench should run north and south. Then mark out a 2 ft. strip along-side the trench. From this strip dig out three separate spadefuls of soil across the width of the strip and put them to one side. Dig out three more spadefuls and put them into the first trench. Spadefuls A and B go in the trench side by side, and spadeful C is put on top. Continue down the strip, digging in this manner, and gradually a ridge will be formed. Mark out another 2-ft. strip, and continue the operation until the whole plot has been ridged. The ridges should be parallel and never more than 2 ft. wide.
Well-rotted compost can be put at the bottom of each trench in exactly the same way as for bastard trenching or double digging, so that ample organic matter will be present when the land comes to be cropped the following year.
Although the normal fork is almost entirely used in the spring and summer, a broad, flat-tined fork is best for digging very heavy clay soils in the autumn. The object of forking is to help break down the soil in the top 4 or 5 in. and thus aerate it. Plunge the fork into the soil at an angle of about 50 degrees, lift the soil and if possible invert it a little when dropping it back. It is useful to put a line across the plot and then to fork over an area about 3 ft. wide right across, then move back the line another 3 ft. and work over this new area, and so on until the whole plot has been forked.
ROLLING OR TREADING
Once the land has been forked in the spring it may be necessary to roll it with a light roller in order to consolidate the soil a little and to prevent it from being ‘puffy’. If land is too loose it may dry out too quickly and the plant roots may be unable to get proper anchorage and to collect the food they need. Forking and light rolling are often both necessary; with a light roller the soil will be left less firm than it was before forking was started.
Rolling also helps to break down any lumps of soil there may be and to leave the soil level, thus making it easier to carry on the next operation, which is raking.
If a light roller is not available, then the plot can be trodden carefully from one end to the other. When doing this, adopt a sideways and shuffling motion so that the whole of the land is evenly trod. This work can be done more easily if squares of wood are strapped on to the boots. Treading done in this way is useful when preparing a seed bed.
The purpose of raking is to break down the top half-inch or inch of soil into particles that are finer than grains of wheat. Raking normally follows the light rolling or treading which has already made the soil level, and the fine tilth it should produce is then suitable for seed drills.
The work is done by running the teeth of the rake evenly and at the same depth through the soil, in a backward and forward motion, and also to the left and right if need be. If the work is done carefully no mound of soil will be left when the end of the plot is reached.
Dutch hoeing should be done, if possible, every week-end until the end of June. There is no point in waiting until there are weeds, for if the hoeing is done regularly the weedwill be killed just as they start to germinate.
Move backward while hoeing, so that all footmarks are removed.
Use the Dutch hoe between rows of vegetables and herbs, between plants in the herbaceous beds or between roses, and use it from spring till early winter. It should not, however, be used on heavy soils between the beginning of November and the end of March.
The Draw Hoe
Whereas the Dutch hoe is used on weed seedlings, the draw hoe is required when weeds are 2 or 1 in. high. Use it with a chopping and dragging action so that it cuts through the soil and the weeds and chops the weeds out.
The draw hoe is also used for getting out seed drills of the right depth. Stretch a line across the plot and- keep it taut. Draw the hoe blade along the line so that its corner can scratch out a V-shaped drill half an inch or even an inch deep. Carry out this operation while walking back-ward.
It may be necessary to ‘peck’ at the soil to make certain that the drill remains at the same depth all the time.
Mulching is generally the application of a thin layer of organic matter over the surface of the ground, first to prevent the evaporation of moisture from the soil, and second to smother annual weed seedlings and so prevent them from growing. Mulches are sometimes used to protect the roots of plants from cold or heat. They may also be put along rows of strawberries to keep the fruit clean.
For soft, bush or cane fruit a mulch in the form of clean straw a foot deep is often used all over the ground, for the flowering shrub border, use leaf mould to a depth of 5 or 6 in. For, heather beds, primula, iris and Michaelmas daisy gardens use really old compost or sedge peat. Grass mowings can be applied as a mulch along rows of runner beans and , but should never be put deeper than J in. because they heat up and so cause trouble to the stems of plants.
Wide strips of black plastic film and heavy grade aluminium foil can also be used as mulch, though organic materials are preferable as they gradually decay and so add humus to the soil.
Do not apply a mulch too early in the season or in frosty weather, as it will retard the warming of the soil. It also lowers the night temperature of the air immediately above it, a point of importance where plants of doubtful hardiness-are concerned.
Make sure that the soil is moist before applying the mulch. Remember that a mulch, as well as conserving soil moisture, may act as a barrier to light rain.