Soil: what’s in it anyway? If you’re exploring the science of gardening this summer, you must explore the basis of garden life, and that’s garden soil.
Ask a child what plants need to grow and they will often mention water and light. After some thought about what’s around the plant’s roots, they might mention soil as well. Often we consider soil to be the place where plants get water, and nothing more. But soil is much, much more than a place for water to hide. It’s a hive of activity, even if this activity is hard for us to see with the naked eye.
It’s relatively easy to explore the big animals that live in the soil. Children likely know that snails, slugs, and worms help recycle plants and animals into soil again. If you want to explore these larger recyclers, find someone who has a worm bin or make one yourself. These small and simple compost bins are a good lesson in soil production. Drill holes in the bottom of a plastic bin and add shredded newspaper to the bottom. Add food scraps. Find red wriggler worms or purchase some composting worms. Place more shredded newspaper on top. Watch the worms over the upcoming weeks as they change your food into soil. What do they like to eat?
These big invertebrates are just the very tip of the soil life mountain. In the soil are millions of tiny organisms that we can’t see very easily, and all of these organisms are helping plants grow. Gradually, these microorganisms and fungi take nutrients from decomposing leaves and other garden waste and make these nutrients available to plants. They help cycle carbon and nitrogen through the garden. How many hard-working bacteria are in a cup of soil? The number is approximately the number of people on earth. Never fear, these bacteria are working in your favor.
How can you see these creatures? To find fungi, look into a decomposing log. You will see many tiny white hairs. These are the mycelia of the fungus, similar to the root system of a tree. They are gradually breaking down the log. Your soil contains these too.
Sometimes you can see soil microorganisms by looking at soil under a microscope. If you don’t have a microscope available, you can visit the Soil Critters web site to take a look at their videos of soil microorganisms.
Soil is a lot more than dry brown stuff. Take a look into your garden this summer, and look down to see one of the most amazing materials on earth.