The best feeling of spring involves plunging your fingers into sun-warmed soil.

Although this wet, dreary winter seemed intent on never ending, now, at last, it’s fled – and the soil has become inviting again. Dirt-under-the-nails days yield immense satisfaction, and I personally feel the greatest connection with life on earth when my hands dig into soil.

Life is complicated; so is soil chemistry. Take the mystery out of that chemistry by sending fresh, dry samples from your lawn and garden for testing to the University of Missouri Extension Service.

By doing so, you’ll learn how much and what kinds of fertilizer to apply for maximum plant performance. This, by the way, truly represents a case of more not being better – don’t guess! (Easy instructions appear online from the MU Extension, whose website also offers a free downloadable 22-pager titled Lawn and Garden Soil Test Interpretations and Fertilizer Recommendation Guide.)

Double-dig any new planting beds. Break chunks of soil with a standard garden fork to the full depth of the tines, spade the soil onto a tarpaulin and then begin again, going two full fork-depths deep. Supplement the soil with organic materials – compost, shredded bark, mushroom bedding, manure, old hay – and add lime if indicated by soil testing.


After that, refill the beds, mounding several inches above the original soil line, and wait at least a week and a rain for the soil to settle before taking any further action. Don’t try to do everything all at once – Rome wasn’t built in a day, and the same holds true for quality loam.

Despite millennia of human-garden interactions and the humor of the expression “older than dirt,” many new ideas about restoring and improving soil keep coming.

Like the human biome – the millions of bacteria on humans’ skin and in humanity’s collective gut – soil nurtures invisible populations: in addition to the expected earthworms and ants, multitudes of soil-dwelling bacteria and fungi. Regarding bacteria, in fact, research continues into how to harvest and use nitrogen-fixing varieties instead of chemical fertilizers. Similarly, debate rages on the merits of biochar (similar to activated charcoal) as a way of building soil structure and locking more carbon into the ground.


For more insights and enlightenment, visit the free Plant Doctor desk at the Kemper Center for Home Gardening at the Missouri Botanical Garden, or email soil questions to plantinformation@mobot.org.

That said, in closing, consider a few special soil-related tips:

  • Never work soil when it’s sopping wet – you run the risk of making bricks.
  • Make sure the water in your garden faucet isn’t connected to your water-softener lest you douse your garden with toxic (and expensive) salt.
  • When using nitrogen fertilizer, buy the more expensive slow-release form, as more of it will end up in your plants and less in the nearest waterway.
  • Keep your biomass at home! Set up a composting system and a worm bin; you can never add too much compost or worm castings to your soil.

All things considered, now marks an extraordinarily exciting time to be a soil scientist – but I confess I just want a hands-on, dirty-nails day in my garden!

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