Browns + Greens + Moisture + Turning + Time = Compost
Simple, right? The actual formula would combine the perfectly exact amount of carbon, nitrogen, a little high quality H20, air, and heat, but I'm breaking it down to Allison terms. Easy.
Researchers John A. Biernbaum & Andy Fogiel from the Department of Horticulture at Michigan State University describe composting like this; 'Making
compost is managing a microbe farm. All
it takes is food, air, and water, just like for any other farm animal. The food does require a certain degree of a
balanced diet as for any other living creature.'
Remember the good old-fashioned food pyramid? It was stamped on every box of food to let us know the right number of servings for a healthy, balanced diet. Your compost needs a balanced diet as well.
Below is a list of foods to feed your pile - it's not all inclusive, but gives an idea. I like to think of the 'Browns' being dry and dead, and the 'Greens' wet and living.
Browns (Carbon):
Dry Leaves
Dry Hay
Dry Grass Clippings
Dry Corn Stalks
Straw
Sawdust (from untreated wood)
Nut Shells
Shredded Paper (watch for toxic ink)
Shredded Cardboard
Paper Tubes
Greens (Nitrogen):
Vegetable Scraps
Fruit Scraps
Coffee Grounds w/ Filter
Tea Leaves w/ Bag
Fresh Grass Clippings
Plant Trimmings
Garden Weeds
House Plants
Chicken Manure
Eggs Shells (neutral)
Some Things NOT to Compost:
Large Wood Scraps (long break down time)
Treated Wood
Colored Paper (be careful for metallic or toxic ink)
Meat Scraps
Fish Scraps
Bones
Dairy Scraps
Baked Goods
Pasta
Cooking Oil
Greasy Foods
Heavily Coated Paper
Aluminum Foil
Dog or Cat Waste (if garden is for human consumption - USDA Study)
Plastics - Recycle!
Now, there are two different kinds of compost. 'Hot' compost takes a little bit of manual labor and the process of decomposition is complete in about two months. 'Cold' compost can take up to two years to decompose, but takes minimal effort- basically throwing everything in a pile and leaving it. Today we're talking 'Hot' compost.
Per scientific studies, your compost pile should be fed a ratio of 25-30:1 Carbon/Nitrogen. Breaking it down to Allison terms; 2 buckets of Browns for every 1 bucket of Greens.
Excessive Browns will cause your pile to dry out and decomposition to slow down. At the same time, excessive Greens will cause the pile to become too wet and result in ammonia gas releasing- stinky. No one one likes a stinky pile. I don't even like to say stinky pile. Stinky pile. Eww.
Monitoring the moisture will help prevent the stink and keep the composting process speeding along. If you notice your pile becoming too wet, add some Browns. If you notice it becoming too dry, add some Greens or simply sprinkle it with a little water.
Alright, we've covered food and water, now let's talk about air. Bacteria is going to break down your pile of scraps, and that bacteria needs air to survive. You don't want to have a smooshed, flat pile and think that just because it's surrounded by air, that will be sufficient. A 'Hot' pile needs air on the inside too. The pile should be nice and fluffy. This can be done by mixing and fluffing your pile with a pitchfork, or by using a fancy compost tumbler.
The last thing the pile needs is heat- after all, it's called 'Hot' compost for a reason. The internal temperature of the pile should be about 140 to 160 degrees F. You can purchase a compost thermometer for around $20.00. It takes about 2 weeks to generate a good amount of heat, and during those weeks you'll need to turn the pile at least five times in order to distribute the heat through all of the materials and keep it at the correct temperature.
I'm going to add scary factor in here. If it gets too hot, it can combust. Yea, apparently that happens in real life. All I can picture is walking outside to a magic fire like I'm Khaleesi in Dragon Land or something. You must turn the pile.
When the pile is no longer generating heat, the process is almost complete (and now I'm Dr. Seuss), it just need to sit for a couple of weeks to cure.
Which leads me to the final ingredient; time. I like to quote Jim Morrison... 'If you book them, they will come.'
Tips to speed decomposition process:
Mass: Pile size should be 3x3 minimum
Material Size: Keep Browns & Greens shredded and chopped to small pieces
Temperature: Keep it 140 to 160 F
Breathability: Shake, rattle & roll - aerate that thing!
Mix it Up: This isn't a layer cake, it's a tossed salad
Moisture: Not too dry, definitely not too slimy
Lastly, how do we determine when we have the final, completed product? The process is completed is when none of the materials are recognizable. No leftover carrot chunks or pieces of straw, and definitely no sprouted weeds or plants.
Another suggestion is to scoop up some compost into a mason jar, add water until it's soggy, twist on the lid and let it sit for a week. When you open the jar, it should smell earthy. If it smells icky, it's not finished.
So, now that we've got the 'how' to compost taken care of, where does this process take place? A homemade wooden box? A wire mesh bin? A store-bought composter? There are tons of options, so check back tomorrow and I'll show you how I made our cheap, easy DIY compost bin.
