Whether in garden or allotment, digging must be thorough especially if soil is being turned up for the first time. The right time for digging is the late autumn, so that the winter snows and frosts can purify (sweeten is the gardener’s term) and break up the clods, making it easier in the spring to get the necessary tilth or fineness forand for growth.
Dig with a spade, not a fork, as the fork is primarily a tool for loosening soil that has already been turned over by digging. A stainless steel spade is best. Trenching or digging to a depth of three spits is an old-fashioned practice which is laborious and in most gardens, quite unnecessary.
Digging is of various kinds: single spit, double spit (a spit is a spade’s depth) or bastard trenching, skimming, ridging, as may best suit the character of soil and what is to be grown. Always be careful not to bring the subsoil to the top as it is invariably less fertile.
Where the soil is found to be of good quality and shallow-rooted plants are to be grown on that particular plot, single spit digging can be adopted, though mostly double spitting is best. Or, it may be, the soil itself is shallow and there are stones below the depth of one spit. Dig out a spadeful and put it beside the line of working; the second spadeful is thrown into where the first one has come from and so on down the length to be dug. Having dug the length, put the soil of the first spadeful of return line into the vacant end of the first trench and work back. Start again at the far end and continue till the required width is turned over. In single spitting, manure is simply dug in and freely mixed with the soil, never placed in separate layers.
Here the digging is to double the depth of the spade. Dig out one spit, put it aside as in single spitting, then dig, but do not bring out, the second spit. Instead turn it over, break roughly and dig in someor grass . Proceed in this way to full length, filling in as proceeding, and then bring the first spadeful to the end, continuing thus till plot is dug. By manuring the lower spit at this stage considerable digging is saved in the spring, and only surface manuring will be necessary, whether by compost or artificials.
This operation refers to the slicing off of turf where virgin soil is being dug. Where there is a good depth of soil and particularly if compost is scarce, the skimmed turves are placed aside and stacked, grass down, in some corner exposed to the weather so that they can rot and provide compost for future use — not less than a year later — when they have rotted. The uncovered soil can be treated by any of the methods described for digging. To skim turf, cut with the spade to 2 or 3 in. through the surface for the width of the spade and for about 18 in. length on either side, insert the blade of the spade into the width cut, easing up the turf till the spade can be thrust along almost flat to free turf for the 18 in. to the depth of the grassonly. Go on in this way till area required is ‘skimmed’.
Ridging. This applies mainly to cultivated, heavy ground. After lifting crops, dig over but do not leave level. Work up into a series of ridges, much as when earthing potatoes, and so expose a greater area of soil to the beneficial effects of frost and weather.
In whatever class of digging, it is better to get rid of the weeds as you proceed. If ignored they will multiply so quickly as to make the labour tenfold the next year. Small weeds can be composted or dug in, but those with large or deep roots must be extracted, roots and all, and burned. Inexperienced gardeners dig too long and too furiously. Do half an hour steadily at it, then rest the muscles by getting out the stones and deep-rooted weeds; do another half-hour, and then take another rest for 10 minutes.
Always clean and polish the spade after use; it makes all the difference in working.
The Ministry of Agriculture, in a leaflet, advises on digging. The following is a succinct epitome.
When double digging any plot of regular shape, such as a io-rod allotment, it is best to divide it lengthways into two sections. Begin by taking out a trench across the end of one section 2 ft. wide and 1 ft. deep. If turf is present, pare it off about 2 inches thick and, together with the excavated soil beneath, remove it to the adjacent section, where the work will finish. The exposed subsoil is then forked up to a depth of about 10 inches, and on this the turves taken from the next 18 in. width of the land are placed grass downwards. The second 18 in. width of top soil is then slug to a depth of 1 ft. and thrown forward onto the inverted turves, and the sub-soil forked up. This process is repeated throughout the length of the first section, and the second section is then similarly dealt with. Complete the work by filling up the working trench with the soil taken out of the first trench on the first section. The double digging of land already under cultivation proceeds in exactly the same manner except that, in place of the turf, material from the compost heap or waste plant material is placed in the trench on top of the broken-up subsoil.
It is important to remember that the digging of heavy clay soils should be done when dry in late autumn, so that the full benefit of frost action in breaking it down to a fine tilth can be secured. Loamy or sandy soils can be left later, but all soils are better for early digging so that they are well consolidated byand planting time.