Compost 101 (Just do it)

In a very random Instagram moment over the weekend—a hastily shot story made while practically running past the compost as I dashed around trying to get a few jobs done before it rained—I showed an exciting compost-related development: a second bin!

Not one bin but two! For a gardener, this is like putting a giant addition on a house.

OK, very few things related to compost can possibly be classified as exciting, but it’s the small things, right?

What I wasn’t expecting was a mini flood of questions about my compost system and composting in general, so I thought I’d just cover it all here in a quick-and-dirty compost basics post.

Compost is decomposed organic material. It is an excellent soil amendment for lightening heavy soil and for adding much needed organic matter. And it’s easy to make.

To be honest, nature takes care of the composting. Everything we do just helps the process go quicker so we can make use of it sooner. 

COMPOSTING SYSTEMS

The simplest composting system is a pile. That’s really all you need. But you can contain compost or pretty it up by using some sort of bin system.

Creating a bin, or a series of bays, helps contain the pile and may make it look a little nicer. An ideal system for a home composter would probably be a three-bay system in which the first bin gets the raw material, which is then turned into the next bin and then into the next bin for finishing and storage until it’s used.

Like a lot of people, I don’t have room that kind of system (or maybe I should say I choose not to make the room for it), so for years I’ve just had one “bay.” Originally I made it out of pallets, which convenient and usually free, but you are limited by the size of the pallets.

About 10 years ago I got these composter brackets and created a 5-foot square bin, which moved several times before landing at what is now the back of the vegetable garden. Last week I bought as second set of brackets so I can have a second bin, which will allow me to make more compost.

The brackets I use come with screws, but you have to add the boards. I leave the top two boards on the front unscrewed so I can slide them out to more easily access the compost. We used cedar 1×6 boards for the original bin. Most of those boards have rotted and will need replacing after 10 years. On the new bin we used treated deck boards. Although treated wood wouldn’t have been my first choice, it represents a fairly significant cost savings and I don’t worry as much about leaching in compost since there’s a lot of decomposing that happens before compost is near my food crops. However, the boards were just a touch too thick (see below) and we had to saw a groove into each board to make it fit. It wasn’t hard, but it’s something worth noting.

There are also compost barrels that can be turned to quickly create a small amount of compost. These also have the advantage of ensuring that no critters will get into your compost.

You can also simply dig a hole and compost in place in your garden, or create a sunken “bin” by digging a hole in the ground.

Hopefully you get the idea that there are a lot of ways to get to the end goal.

HOW TO MAKE COMPOST

No matter what kind of system you use, the ingredients to make compost are the same: carbon-rich “brown” material, nitrogen-rich “green” material, water and air. 

A Google search for the ratio at which you should add browns to greens in a compost bin is anywhere between 2-to-1 and 30-to-1. I say, don’t stress about it too much. You should have more browns than greens. If the pile gets slimy, add more browns, if not much is happening, you probably need more greens.

If you’re using a bin, it’s helpful to alternate layers, but that’s not always possible (like in fall when it seems like it’s all brown). 

You need moisture to get decomposition happening, so a good soaking so that the material is about as damp as a rung out sponge usually does it. 

Air comes in by turning. I use a pitchfork and count it as my workout for the day. I probably only turn it three or four times a year. 

WHAT TO PUT IN THE BIN

Here’s what my compost bin looks like right now: a combination of leaves, dead plant material, kitchen scraps and coffee grounds (filter and all).

Here’s the big question: What are you supposed to put in there? Making lists is hard because it depends so much on what you have to work with. Under no circumstances should you ever have to purchase something to put in your compost. I know that sounds weird, but I’ve seen people talk about buying compost ingredients before and there’s just no need. You also don’t need purchased composed “starter” (or whatever they call it). A shovelful of soil from your garden will have all the microbes and bacteria bits you need.

You also don’t need to add worms. Worms and all the other things that make decomposition happen will find your compost if it’s sitting on the ground.

Browns:

• Leaves
• Straw
• Dead plant material
• Shredded newspaper, office paper or cardboard (avoid shiny paper from flyers, etc.)
• Coffee grounds
• Egg shells

Greens:

• Grass clippings
• Vegetable scraps from the kitchn
• Deadheaded flowers, pruned material or clippings

The smaller the material you put in, the faster it will break down. There’s no need to get high-maintenance about it (blending your kitchen scraps before you put then in the bin is not necessary), but if you run a lawn mower over your leaves before you throw them in, you’ll speed the process.

What not to put in:

• Meat
• Fats (or vegetables that have been cooked in fat)
• Weeds, possibly*

About those weeds: I am a little careful about weeds in my pile. If your pile gets hot, you’ll cook seeds or roots that could be problematic down the line, but a lot of smaller systems don’t get that hot. I typically try to avoid putting weeds in my pile, especially anything aggressive that is perennial.

I also used to avoid putting diseased plant material in my bin, but then I spoke with Lee Reich (and he knows composting) who told me has always put diseased material in with no problems. 

VARMINTS AND GENERAL UNPLEASANTNESS

The No. 1 reason I hear from people who are reluctant to start composting is a concern about rodents and odors. Odors are easy: Your compost pile should never smell foul. If it does you should add more browns or give it a turn.

As for varmints, I have to say, I’ve never had a problem. Maybe I’m lucky, but it’s just not been an issue. Avoiding meats and fats will definitely help. Lee puts hardware cloth on the bottom of his bin to keep rodents from coming in so that’s an option too. 

HOW DO YOU KNOW WHEN IT’S READY?

The beauty of compost is that it doesn’t demand a lot of attention. But it does demand some patience. It typically takes me about eight months to make compost, but because, up until now, I’ve had a one-bin systems, that’s not the entire bin.

I manage the one-bin system by pushing aside all the bits that are clearly not fully broken down, and then aim for the middle of the pile. This aerates the pile, but also helps me sift through to the finished compost. 

Compost is finished when it is fluffy and dark and has a slightly sweet, earthy smell. If it smells at all unpleasant, it’s not finished. If you need very fine material, say to add to containers, you can put it through a sieve (half-inch hardware cloth stapled to a frame works pretty well). I usually just pull out bit, clearly not fully broken down material by hand. Usually I just add compost as a top dressing, so it will continue breaking down there.

You can dial in a compost operation to be a fine-tuned machine and watching the process unfold is truly fascinating. But you can also take it at your own speed and make it what you want. 

My advice? Don’t get too caught up in the details and just start. Nature’s got your back.