08 Sep Compost Part two: The Science
Think of composting as “cooking”. In fact, several times during her class, Barb referred to it as just that. If your desired finished product is healthy compost, then you’ve got to start with the right ingredients!
Ideally, you want to combine Carbon-based materials and Nitrogen-based materials in a 3:1 to 5:1 ratio. The other major ingredients in the recipe are water (or moisture) and oxygen. Absolutely no dairy or protein should go into your batch.
Because the process is part science and part art, you may have to play around with your ratios to get the ideal results for your environment. It’s helpful to know some science basics to help you make the adjustment. A few hints are these:
Carbon based materials are usually brown.
Nitrogen based materials are usually green.
Frequent compost items, coffee grounds and tea bags may be brown, but are high in nitrogen.
When your composting is a little too fragrant for your liking, you probably have too much nitrogen.
Now, how does one “cook” their compost? Well, first make sure you’ve covered the green materials with brown materials. Add enough moisture (or allow for natural moisture to make its way into your bin) so that your compost materials are fairly moist, but not wet. Lastly, make sure your materials are exposed to plenty of oxygen. The microbes that break carbons and nitrogens down into compost require oxygen to do their thing.
If that’s all you do, and if you have some hot weather (ideal temperature inside your bin should be about 140 degrees, Fahrenheit), you should be okay to sit back and wait for your compost to be done. Just remember to check on the moisture. It may take some time for your materials to break down into usable compost. If you want to expedite the process, you can “turn” the compost (either in a tumbling bin, or by shovel/hand).
Your compost bin will get quite hot, but home-composters will almost never get hot enough to destroy really stubborn items. So, if you’re going to compost eggshells, make sure you’ve crumbled them up. They won’t break down completely, but will provide an excellent source of calcium for your new soil. (This is especially good for spreading on tomato plants!)
Another thing that probably won’t compost for you is anything that has gone to seed, or anything that has diligent roots. Other things to avoid? Black walnut, too much citrus, and anything that’s bad for YOU (duh) like pesticides or feces!
If you’re going to build your own bin (aren’t YOU handy?!), the ideal dimensions are at least 3 cubic feet. You can use a multi-bin system to make your work a little easier. A three-bin system is perfect. You can keep the start of your batch in the first, turn that bin into the second, and “cure” (or perfect) the batch into the third.
If you’re like me, and you’re susceptible to a little laziness, you will be happy to know that you can also compost via mulching! It will take some time (and will likely not be too pretty), but it will work. Simply use leaves and yard waste as mulch in between your plants. You can occasionally rake it to make it more attractive. And when inspiration does strike you, you can build a furrow between your plants. If you add kitchen scraps to the furrow before winter, they will decompose and add nitrogen back into your soil.
All in all, the whole thing is so easy (and so natural), it made me wonder why I was intimidated by it in the first place. In fact, in the few weeks it has been since part one of this blog, my compost shows no signs of banana peels or coffee grounds! Now if I can just convince Samantha that since I made the compost, SHE has to spread it…
As always, TELL THE TALE!