The other day I was digging a trench to run water into the new laundry here at Earthaven. The trench was to be at least 18″ deep to get it below frostline and had to run about 25′ to the main water line and remove enough earth to be able to tap into the main water line. All told I would remove over 37 cubic feet of earth (about a third of a ton) – mostly red clay. Fortunately, the red clay was soft and the spade could slice through it easily. It would take me three hours working at a moderate pace to accomplish.
My spade blade is 9″ wide by 12″ long. It would take two blade lengths to get deep enough. One spade width is sufficient. I also only took about 6″ bites to keep the load lighter just in case any rocks (which weigh about 100lbs per cubic foot) should appear in that blade full of earth.
To reduce strain on the handle I can only put the blade into the ground as far as the shoulder on the blade and use the shoulder to lever out the blade full of earth.
If your blade isn’t sharp you may find yourself jumping on the shoulder of the blade to get it to cut into earth. If your blade isn’t sharp, on soft ground this won’t be necessary and only stepping on the shoulder will suffice.
I will dig using what I call “steps” where I start (after digging the initial hole) by taking out 2 loads one blade length down from the ground surface and then 1 load down from that step. I then do one from the top and one from the step – keeping this rhythm going until I reach my destination.
The earth is placed uphill from the trench to make refilling it easier and to not lose the earth in the grass and plants down hill. It will also help to keep run off from any rain from filling the trench until the line is actually in place.
For choosing a spade or shovel, or to learn more about them, see my article on Selecting and Using Tools: Shovels