Thursday, July 17, 2008

Home grounds

Another way to transform coffee grounds:

'Bumble Bee', 1997, acrylic paint-charcoal and coffee grinds on canvas. Copyright Elisabetha Vanderheide; contact artist for commercial use:

Though my students, and fellow teachers in our coffee club, may find this hard to credit, during the summer I only drink a cup a day. I guess that's one difference between getting up at 5 a.m. and spending the day with teenagers and getting up when the spirit moves and spending the day with plants.

Part of the morning caffeine ritual is the tossing of the grounds. I amble out to the front yard and decide which of the acid loving bushes gets the largess today. Usually it's a blueberry, but I also have a rugosa rose out there, some azaleas, and native bunchberries that are spreading out to carpet the shadiest spot.

I love doing this, but I did start to wonder if I was actually accomplishing anything besides adding to my eccentric reputation among my neighbors, so I did a bit of research.

A list of Top Ten Things To Do With Coffee Grounds, suggests rubbing them on furniture scratches and strapping them to your cellulite with plastic wrap (evidently the caffeine does something magical to those little bumps, and if not, you can still smell like a Starbucks, and we all know how sexy that is.) Moving on to more complex projects, to see a pickup truck that runs on gassified coffee grounds, check out
You can also buy fuel logs made of compressed grounds and wax. Java-Logs are the invention of a Canadian engineer who determined that they burn hotter and cleaner than Prestologs. On a larger scale, I learned from Food and Grocery Information, Insight and Best Practice, that Nestle's in England generates steam to power its instant coffee plant by burning coffee grounds.

Back to the garden: After reading many, many lists and tips of sometimes dubious provenance, I found out that Cooperative Extension in Lane County, Oregon, is doing research that can move us from folklore to reliable information.

Cindy Wise, the coordinator for Extension's Compost Specialist program in Lane County, heads a group of Compost Specialists (a label I would love to earn) who collect more than 50 tons of grounds per year from area coffee shops. Their experiments indicate that the nitrogen-rich coffee grounds can be an effective substitute for manure in compost piles, supplying the heat that is needed to kill pathogens and quickly break down organic materials. That's been an issue for me since I moved off the farm and no longer have easy access to animal doo.

"In the trials, when coffee grounds made up 25 percent of the volume of the compost pile, temperatures were sustained between 135 degrees and 155 degrees for at least two weeks, enough time to have killed a "significant portion" of the pathogens and seeds, Wise said. In contrast, the manure in the trials didn't sustain the heat as long, she said."

I also learned that I'm probably missing the point by concentrating on the acid-loving plants. The acid in the beans goes into the coffee we drink; the grounds are pH neutral, pretty much. Furthermore, the nitrogen in the grounds is not immediately available to the plants, so it makes more sense to use the coffee to boost the compost pile and then put the compost on the garden.

I enjoy my morning ritual, though, so I may continue to put that pleasure over practicality. Maybe I'll find a nearby coffee-swilling household who will give me their grounds for the compost.

To read the full Cooperative Extension article, see

The Community Co-op sells Java-Logs.

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