Composting Isn't a Waste

Compost makes me think about life's basics. Compost is decomposed (waste) plant matter. It's in the dirt under our feet. We wouldn't be alive, of course, if the soil couldn't sustain us -- to grow the food we eat.

Common sense may say that if one takes stuff out of the soil (for growing food), then one should put something back in. If nutrients in the soil (food plants need) are depleted, then we will not have healthy plants. And that means the food we (humans) eat may not have all the nutrients we need either.

So going back to compost... it is what we put back into our soil. It's overly simplistic, but if the compost also consists mostly of plants we took out of the soil, then the compost should have mostly what the plants need to grow, right? At least that's how I make sense of it.

In our home, the vegetable and fruit scraps all go into our compost bin -- banana and apple peels, broccoli stems, including egg shells (calcium). The plants and leaves that I cleared from our yard and garden, also get chopped up, and go into the compost.



Stuff like coffee grounds and tea bags can go in to the compost as well. Did you know that Starbucks (the coffee company) has used coffee grounds that you can take away (for free)?



In our urban environment, we have a compost bin that looks like the one below. We purchased it from the Los Angeles County Department of Public Works. It's made of plastic, and about 2 feet x 2 feet in size, and has a sliding door at the bottom to remove the composted material. One could probably just make a compost pile, but a container helps to keep rodents and other creatures out.

For people living in apartments, one can also create compost with a "worm bin".



I was curious, so I stuck my hand inside the compost pile to dig around. Yes, there's biological decay going on. There's earthworms too, and the compost is actually quite "warm" inside. How warm is it (you might ask)?



Using a digital multimeter I found out the temperature. I inserted the probe in the center of the compost bin (about one foot inside) for a mass of compost that's about two cubic feet (2' x 2' x 2'). The measured temperature was 30.5 degrees C (87 degrees F). That's warm considering the outdoor temperature was only 57 degrees F at the time.



For me, this shows me that there activity with billions of microbes working away on the compost. There's more going on than we realize. Here's one link to the Science of Composting.

Eventually, this compost ends up back in our garden, and the plants seem to appreciate it by the way they grow.