My 3-year-old daughter Poppy loves her earthworms. She will pluck one up from the soil, balance it carefully in the cupped palm of one hand, and keenly watch it writhe around. Then she will place it on a leaf, pretend to change its diaper and finally return it to its “worm family.”
Earthworms might seem unlikely desert companions. But they thrive in our worm composting bin. Also called vermicomposting, worm composting uses earthworms to break down food and other organic waste into nutrient-rich soil. This composting method is popular in cities, because it doesn’t require much space. It can be set up in a plastic storage bin — or even a shoebox.
Our family’s own 10-gallon bin sits half-buried in the ground in a shady spot in our backyard. It’s filled with moistened peat moss, shredded coconut fiber and cardboard. Food scraps rest on top of this worm “bedding.” Earthworms move freely throughout. There are about a dozen holes drilled into the sides of the bin for air, and a dozen more in the bottom for drainage.
Red wigglers — not the night crawlers sold in fishing stores — are best for worm composting. We got ours free from a worm composting workshop, but like anything, you can order them online. The Arizona Worm Farm (arizonawormfarm.com), 8430 S. 19th Ave. in Phoenix, also offers classes and sells composting worms.
Health benefits
Getting kids outside these days can be a challenge. Screen time is a new family reality. Poppy loves to compose emoji messages to friends and family on my smartphone. It’s cute, but a little alarming. The 2019 census by Common Sense Media found that 8- to 12-year-olds spend an average of about five hours a day on screens — not including time at school or doing homework. And while Poppy will dive for the TV when allowed, she will also dive for the back door when I mention visiting the worms. I know that worm time means she’ll be outdoors, absorbing biorhythm-regulating sunlight and working toward those three hours of physical play per day recommended for preschoolers by the American Academy of Pediatrics.
The health benefits of a worm bin aren’t just related to getting outside. Some exposure to dirt may actually be good for young kids’ immune system development. According to a 2016 study published in the New England Journal of Medicine, exposure throughout childhood to the kinds of microbes found in agricultural settings led to lower incidences of asthma and allergy.
Another study by the National Academy of Sciences has shown that adolescents living in homes surrounded by a wide variety of plants and animals were more likely to have a diversity of microbes living on their skin, which was also correlated with a lower incidence of allergies. And, while researchers don’t yet understand quite how it functions, the soil microbe Mycobacterium vaccae is involved in the production of the hormone serotonin — one of our most important happiness hormones.
STEM lessons
Working with red wigglers can teach kids of all ages about animal biology and ecology. Children will feed the worms dinner scraps, only to find that the scraps disappear into new, dark dirt. How does this happen? Does it happen in all types of landscapes? Is anything else breaking down the food besides worms? Will a houseplant fertilized with this worm compost do better than one that is not? Answering these questions presents an opportunity for research, experimentation and learning.
Older kids can learn engineering and math skills by designing, measuring and constructing worm bins. Besides the drilled-holes-in-a-plastic-tub method, bins can be made out of wood planks or old scrap material. Children will need to research and consider where to place air and drainage holes, what kinds of worm bedding work best, and a how to position the bin so it won’t bake in the heat. (Note: Full shade is not enough for worms to survive an Arizona summer. Sinking the bin into the ground or bringing it into a garage are two options.)
Finally, kids can learn a sense of responsibility from feeding their “pets,” checking the bin’s moisture level and retrieving finished dirt. They will learn how composting keeps food waste out of landfills and turns it into valuable fertilizer for farmers and gardeners. They can even make money selling the nutrient-rich soil produced by the worms. And according to research by University of British Columbia’s Catherine Broom, kids who play outdoors are more apt to want to protect nature as adults. Overall, worms are relatively stress-free pets that foster learning, responsibility and good health for kids.