The Dirt

Our after school Garden and Cooking Club got into the dirt this week, literally. From tilling the soil to starting our first compost pile (pictured) to building our own Worm Café to some simple pH tests to figure out how to feed and replenish what was used up by last year's plants, we've been hands deep in the dirt (and the weeds) for the last two weeks! Along the way, we learned what a wonderful rich story every square inch of soil has to tell and we thought we'd share a few of the most fascinating facts with you.

What exactly is dirt?
According to our book on soil, soil is "the naturally deposited unconsolidated material which covers the earth's surface whose chemical, physical, and biological properties are capable of supporting plant growth." Huh? Deposited unconsolidated material, eh?  We love the SAT-worthy words, but we wanted to find a simpler definition so we surfed over to Websters Kid's Dictionary and found this:

soil (noun):
i. firm land
ii. a : the upper layer of earth that may be dug or plowed and in which plants grow
b : the superficial unconsolidated and usually weathered part of the mantle of a planet and especially of the earth
iii. country, land <our native soil>
iv. the agricultural life or calling
v. a medium in which something takes hold and develops

Definitions 2 and 5 seemed closer to what we think of when we talk about the soil in the garden. Still they still did not quite give us the simple straightforward definition of soil we were hoping for--and maybe that's because soil is so much more complicated than we give it credit for! It's literally teaming with life and essential to helping new life translate sunlight into usable energy. Soil is a crucial part of nature's recycling system and critical to the food web that we all rely on. For now we're consider soil as the living, breathing outer layer of the earth that's made from all kinds of materials (plants and rocks and vegetation and animal matter) in various stages of decomposition that provide habitat for new plants and animals.

Soil as we know it today has developed over an extremely long period of time; in some cases even thousands of years. It's one of the earth richest resources and it's also one of our most renewable. But it does require some care, especially when we put it through rigors like farming and remove its natural rehabilitators (like forests) from its surface. So, we've been testing the soil in our 39 rooftop planters and are getting ready to feed it with…you guessed it…worm poo! Feeding the soil is on our "to do list" for next week's gardening club.

So until then, we'll leave you to contemplate this chart that shows how soil fits into a complex food web plus a link to some great further reading about the basics of soil from CXI. We really like how they define Soil as "a complex habitat where plants and microorganisms live together. Healthy, living soil is alive with a diverse population of microorganisms including bacteria, fungi, algae, protozoa, and nematodes. These organisms create a web of activity that decompose organic matter in soil to ensure that nutrients are usable by plants and crops. This results in continuous soil development, maintenance of soil structure, nutrient cycling, and various beneficial interactions with plant roots."