So you have ordered your coffee, pulled your shots and enjoyed delicious espresso nectar from your Five Senses coffee. What now? How about returning those coffee pucks and filter grinds back to where it all started in the form of composting — adding some organic goodness to your garden. Correct composting needs three things; food, air and moisture. Here’s the low down on how to make perfect compost with your garden, household and coffee waste.
For good compost, a balance of ‘brown’ and ‘green’ material is required. These materials are a good source of energy for the compost microbes which in turn break down the compost and improve aeration. Brown material can be things like dry leaves, straw, shredded paper, sawdust and dried weeds. I use roasting chaff for my compost ‘browns’ which works a treat; dry lawn clippings could be a good substitute. Green materials include kitchen scraps, green leaves and, of course, coffee grinds and pucks (filter papers compost just fine too.) Green materials are usually fresh and/or contain moisture. Green lawn clippings can also be used, but note that you should allow the compost to break down thoroughly. Lawn clippings can have a negative impact in causing water repellence. As a rough guide, add two thirds ‘brown’ food items to one third ‘green’ items.
Meat, bones and fatty food waste, diseased plant material and pet faeces should never be added to compost!
Good aeration is critical for composting. Turning the compost frequently (every few days) using a compost tumbler is a perfect way to achieve this. Aeration allows the microbes to operate properly and it also attracts the right kind of microbes (aerobic as opposed to anaerobic) to your compost. Well-aerated compost with the correct mix of food should be sweet smelling and generate plenty of heat. You will see it steaming in winter! If your compost smells rotten this is a sign that either your food mix is out, your compost is too moist or there isn’t enough aeration — which is usually due to not turning your compost frequently enough.
I mentioned this briefly above, but the correct moisture level in your compost is critical to sustain bacterial growth and the breaking down of your food elements into compost ready for the garden. Some of this moisture (and sometimes all) will come from the ‘green’ food items you add to your compost. As a rule, the level of moisture in your compost should make it feel like a wrung out sponge. Adding small amounts of water to your compost is the best way to get the right balance. Check it frequently and make small changes as you go.
Once you have all your food elements together and your compost bin is approximately a cubic meter in size, don’t add any more food to it. Adding fresh food to your compost at this stage will mean that your final product contains bits and pieces in varying stages of decay. This often means that you will get seeds sprouting up everywhere, as the vegetables and other things you have put in haven’t had the time to decompose. From start to finish, the process can take anywhere from 3-5 weeks for a batch to be ready. By the end of the process, you should have a dark brown to almost black product. This colour indicates that you are ready to use the compost in the garden, either straight onto the surface or by digging it into the soil. Another tip is to add a shovel full of regular garden soil to the compost at the beginning of the process — this adds natural microbes to the compost which then grow and multiply. When you are finished with your compost batch and are ready to empty it, leave some in the tumbler. This will ensure that your microbe stock survives to decompose the next batch.
I would highly recommend the tumbler-like compost bins, as aeration is easier (a quick turn or spin as compared to unloading, turning and reloading a bin) and they also keep the compost off the floor which deters rodents.
Coffee is grown in some of the most fertile soils in the world, so it’s no surprise to me that using coffee for composting yields great results. There’s also just that little sense of satisfaction that you are completing the circle by making use of something that would otherwise be discarded to land waste. You also have the pleasure of reliving some coffee aroma in your garden beds and vegie patches — yes, that’s right, the compost does have a unique, pleasant coffee aroma!