Setting aside for the moment the till or no-till issue (regarding the benefits of not turning the soil at all with whatever tool), it is worth thinking a bit about the different results obtained from tilling and spading. For many centuries, spading was the only option on a garden scale, particularly with cheap labour for digging. Modern tools have changed the situation radically.
Spading and tilling have similar objectives; the intention is to rotate the surface soil in place so that soft material is buried and earth that was unexposed to weathering will be brought to the surface to enjoy the tilth-making benefits of frost. Additional benefits are the burying of surface vegetable material leaving soil smooth and vulnerable to efficient raking and seeding, and aeration.
My digging spade is a rectangular piece of steel seven inches wide, eleven inches deep and a fraction of an inch thick. It is attached to a handle, and the blade is forged into a three dimensional shape so that when prying on the soil the tool is able to hinge at soil level and operate on the soil to the full width of the spade. In theory, if the whole of the area of the garden were dug with the spade, every speck of soil to a depth of almost a foot will have been disturbed. The bottom edge of the spade is sharp along its length to be able to sever soft roots, and the top edge is rounded over or has a ledge so that the action of a boot on the blade does not cause premature wear to the gardener's boots. It weighs just a few pounds, is easy to carry and use for long periods, and strong enough for the heaviest soils and weed infestations. It needs little maintenance apart from attentive use and keeping it clean and bright.
My tiller is a machine with curved tines. The tines slice into the soil as the machine moves forward. The diameter of the curve of the tines is about eight inches, but only about two thirds of the tines will be buried at any moment in time as tilling progresses. Tilling requires "headlands" or spaces to turn around where no actual tilling takes place. The tines keep their sharpness as they travel through the soil, slicing into roots and plants as they are met. The machine is heavy and difficult to manoever, especially when not under its own power, and liable to become tangled with weeds when working fresh ground with lots of trash at the surface. Engines can be temperamental, sometimes need professional maintenance, and will react strongly to heavy roots and stones buried below soil surface.
Rotating the soil in place is probably achieved equally well by both methods. Tillers are better at incorporating surface trash and aeration since in fact they take many more slices of soil. Spades go deeper, and where necessary can go to a depth of several feet, although in such circumstances we are better off with a round mouth spade since the point will penetrate lower levels of soil better when they are more compacted. A spade is also good for edges of garden plots; in my quack grass sod the stolons keep trying to grow from the perimeter pathways into the cultivated garden area, so the spade keeps this under control. The tiller will encourage such weed growth instead of stopping it.
If the garden is relatively clean of perennial weeds and cost is not an obstacle, a rear-tine tiller is probably a good choice. However my preference is for the spade, for the following reasons: exercise, sudden heavy physical demands, weed control, stone removal, attention to perennial garden inhabitants, perimeter weed control.
Digging is a gentle exercise, steady and regular. If a rototiller takes a lurch due to a rock or root it can demand sudden physical intervention, which can come as a surprise. Good if you are fit, not welcome otherwise. Digging is slow; each dig into the soil focuses attention on the weeds and stones it may contain and provides an opportunity to deal with the obstacle. It is an investment in the future. Some garden plants need to be left undisturbed; it is easy to work around them with a spade. I once rototilled right over a valuable (to me!) tarragon plant, burying it completely. Once done the tilling I realized my mistake and was able to locate the area and find a number of rooted pieces and re-establish the plant. But it was unnecessary extra work caused by my inattention, over-confidence that the rototiller knew what it was doing. And even when using a rototiller on a large clean area it still pays to do the perimeter with the spade, paying close attention to migration of weeds into the cultivated area.Copyright © 2016