Why Eight Is Not Enough

Today's confession: I am not always the most responsible organic gardener.
For instance, I've had a few summers' worth of intense gardens, but I've neglected to replace all of the nutrients my corn, tomatoes, and basil grabbed out of the soil. It's not even that hard. All I'd have to do is blend fresh compost, worm castings, or rotted manure in with my topsoil.
Easy as pie. And yet...


My soil's still dark and crumbly, and things grow perfectly well, but I've been wondering if my laziness isn't taking its toll. I could find out with a soil test, but there's another investigative tool that’s more low-tech -- and, I think, more interesting. I would unearth the truth with an earthworm census.

Since they act as miniature tillers as they move through the soil, earthworms dramatically improve soil structure. They do a lot for soil fertility and drainage, too. So it stands to reason that a garden teeming with worms is in good shape.

I recall seeing scads of the wiggly subclass Oligochaeta when I originally dug my garden beds a few years ago, and I hoped nothing much had changed. To find out, I grabbed my bucket and shovel and selected an area that's fairly representative of my garden soil. I dug six inches down in a one-square-foot spot, carefully dumping the soil in my bucket. Then I combed through every last bit of the sample, breaking up the soil between my fingers, and letting the fine particles drop back into the hole -- and hoping to see and count myriad, vigorous worms as I went.

Surprisingly, it was at least five minutes before I saw my first worm, and it was another several before I found another. The final score? Just eight teeny, tiny worms in my sample.

Most organic gardeners agree that finding 10 or more earthworms in a sample the size of mine would be a very good sign. Five to 10 usually counts as passable, and fewer than five? That's trouble. But eight?

To boost next season's census, I'll be adding more organic matter so they'll have plenty to eat, and I'll leave that soil-compacting tiller in the garage so that they can move through the soil with relative ease. Who knows. Maybe I'll break 10 next time around...