Spring has arrived and with it the task of soil preparation for planting. If you have an established plot this could be as simple as sprinkling compost and minerals to rake in. If you’re new it will require a bit more work.
There’s lots of lively debate over the various methods used by both large and small growers. I hope my brief comparison of some of these methods will be helpful to you.
Plowing: When New Eden was first established the former meadow was turned under with a plow. This was appropriate initially to break up thick sod and compacted soil in a large area. It’s not necessary or desirable to plow again now that paths and garden plots are in place and the sod has been subdued.
Cons: Plowing damages soil structure and beneficial organisms that will not recover with repeated use. Topsoil is more susceptible to erosion with deep furrows. This technique uses petroleum fuels that release toxins into the air and surrounding soil. It also requires expensive equipment.
Double digging is promoted by Bio-Intensive growers as a means of creating deep, rich soil with human power rather than petroleum. It requires hand digging to a depth of 2 feet with the sub soil kept separate from the topsoil. Usually done in a raised bed which reduces or eliminates soil erosion. This is a great way to start a new bed in an area with compacted soil, large rocks, sod and weeds. It allows easy incorporation of organic matter and mineral supplements into the soil.
Cons:Soil structure is damaged along with beneficial organisms and mycelium, but they will recover and the double dig is only done once. It is a lot of work for those of us with older spines. Don’t try to double dig near trees or shrubs or you will lose the battle to the woody roots.
Sheet Mulching is an ancient technique that requires no digging except to remove large rocks and persistent weeds such as witch grass. With this method raw compost, manure, seaweed etc is spread on the soil then covered with alternating layers of cardboard and more compostables along with mineral amendments.
This method works well in areas near tree and shrub roots.
Cons: It will take a few months for sheet mulched beds to get to optimal performance. Requires a lot of organic matter and carbon matter to make the initial beds.
Rototiller: Easy and fast way to chomp up a bit of soil.
Cons: Repeated use of a rototiller can create an impermeable hard pan at the level where the tines burnish the subsoil. This sort of tillage mixes subsoil into topsoil to the detriment of both . Petroleum fueled tillers don’t have an emissions standard so we won’t know what they might deposit on the garden beds. I would suggest a kinder and gentler tool for those with established plots…
The broadfork! Which has been promoted by such luminaries as Eliot Coleman and John Jeavons. This is a great human powered tool that we can all use to aerate and loosen the soil without doing damage to our micro system allies. It’s also easier to wield than other implements for those who might not want to dig too deep.
That’s enough for now except to wish you all happy digging!