I discovered this wonderful organic matter about 12 months ago when a friend of mine gave me two large garbage bags of coffee grounds that he picked up from a local cafe. Without thinking too much about it, I added a bag each to two of my three compost bins. About a week later I checked back and to my amazement there were worms in abundance literally swimming though the grounds. They loved the stuff and multiplied quickly, which made me happy.
Anyway, after a while I promptly forgot this valuable lesson until about three weeks ago when I read an article about the benefits of coffee grounds when used in your garden, compost or worm farm and how it has a high carbon to nitrogen ratio (about 20:1) which is comparable to grass clippings. Coffee grounds also help the soil to retain moisture if added directly. For those who compost, it is used as a 'green' and not a 'brown' even though that is its colour. For those who thought it would be high in acid (just like a cup of coffee), think again, because it has relatively balanced pH of between 6.2 to 6.9 (with 7 being neutral). Most of the acid is flushed away during the coffee making process. If you have acid loving plants such as blueberries, you can add it directly around the base and they thrive.
Now I am a one cup a day man, which produces 20 grams (3/4 oz) of grounds. This doesn't sound like much but over the course of a year that amounts to 7.3 kg (16 lbs) of waste. It only takes 50,000 cups of java to make one metric tonne of the stuff, which you can easily imagine many, many times over in a large city of 4 million like Melbourne or Sydney. 1 tonne of coffee waste emits 1.6 tonnes of Greenhouse gasses, primarily being methane (CH4), so that is one hell of a lot of GHG emissions just from coffee waste. Taking it out of the waste stream is doing the climate a favour!
Where do you get a steady supply of this 'brown gold'? Well if you happen to live in Melbourne, which is home of Australia's coffee culture, you certainly do not have to look very far. There are cafes and coffee shops everywhere, just throwing away mountains of coffee grounds every single day. All you have to do is have the courage to ask for them.
So I did ask. I currently have an arrangement with my favourite coffee lady Kate, whereby I take in a little bucket with a lid, and she diverts the coffee grounds from landfill and into my bucket. It fills in a couple of days and I collect it in the mornings and pop it into the boot of my car before I catch the train. A nice arrangement and Kate was more than happy to accommodate me, probably because I started the keep cup craze here at the train station. Anyone who is anyone now has a keep cup (well at least 15 people that catch my train now!). There are many other cafes in town, so it would be easy enough to approach them as well, but we will see how much I get from Kate each week first before I get too greedy. The worms and compost bins can only take so much.
|The coffee bucket for the railway station cafe.|
Additionally, lets not forget our work places. Many now have automatic coffee machines that grind roasted beans and serve up a half decent cup of coffee. I know that at my work, just about every floor in our high-rise has one of these machines that needs to be cleaned out daily. The grounds are usually tipped into the landfill bin by some unconcerning soul. However, the machine on my floor gets cleared by yours truly, whereby I cart the grounds home in my lunch box. The only limitation I have to taking home more is the room and weight of my backpack. I could probably carry about 3kg comfortably and there is certainly much more than that going into the bin each day.
|My lunch box (after lunch of course)|
Best of all, coffee grounds are free!