I spent part of the morning double digging the parking strip. For those of you unfamiliar with double digging, a short primer:
- Strip all the sod off the bed, if there's any there.
- Remove all plants from the bed (if there are any).
- Dig a trench to the depth of one spade. Move all that soil onto a tarp.
- Use a garden fork to loosen the remaining soil in the trench to the depth of a second spade.
- Pour mulch, compost, dead weeds, roadkill, or whatever organic material you have lying about into the trench.
- Move over.
- Now dig a second trench right next to the first, again to one spade depth. Dump the soil from the second trench into the first trench.
- Repeat steps 4 through 7 until you have completed double digging the whole bed.
- Dump the soil on the tarp into the last trench.
- Smooth out soil with a rake, breaking up any clumps. Replant.
- Crawl to the bathroom, take four Advil and a hot bath, ideally followed by a shot of whiskey.
- Sleep like the dead.
Double digging is a method for loosening up compacted soil and enriching it with organic material. There's no question that it does a pretty good job of both of those things. But it took three hours to do about two-thirds of the 8' x 16' parking strip. I almost never double dig, and now I remember why.
Besides the fact that double digging is slow and exhausting, it's hard not to mix up the top soil and subsoil. The top soil is the dark brown stuff that actually supports plant life (and worms and microbes and other things that make plant life possible). The subsoil is the extremely compacted yellow stuff you could use to throw pots. Ideally, you want to loosen the subsoil without actually mixing it with the top soil. In practice, that's nearly impossible, at least when digging a new bed in an Indiana garden.
Also, I'm pretty sure I killed a lot of worms. The more worms in my soil the better, as far as I'm concerned. But you move all that soil around with sharp implements like spades and hoes and whatnot, you're going to chop some worms. The robins are out there having a buffet.
I read about a woman who hired some teenagers to strip the sod off her bed, then bury it upside down 8" below the soil line. This woman was a genius who 1. got someone else to do the labor and 2. came up with free organic materials to enrich her soil. I was unable to follow her example, largely because my trenches weren't that deep. My sod is like the grass of the undead, and I was convinced no matter how deep I buried it, it would rise again, probably while moaning and lurching across the bed toward newly planted perennials. So for now, all those little squares of sod sit in a pile in the backyard, probably planning their assault on the rose bed.
In short, I'm convinced some sadistic head gardener invented double digging to keep his underlings busy and out of trouble. As I have no underlings, I will not be double digging the remaining one-third of the bed. Instead, I'll loosen up the soil with a garden fork. When I plant, I'll dig extra-wide holes and amend them with lots of compost. Then I'll top-dress the bed with compost and let rain and the worms work it down into the soil.
Leave the digging to the worms. It's their job.