Composting: How, What, Why, and Questions

In answer to several questions and requests, as well as the incredible amount of interest in the backyard garden thread, here's an easy guide on composting that I wrote up. It's nothing fancy, but basically just addresses the how-to, most common questions, and things I learned from my own mistakes, or the advice of those who've gotten really good at it. I am not the end-all, be-all expert by any stretch of the imagination, and absolutely welcome any additional advice any of you can give.

WHY COMPOST:

If you live in an apartment, composting may be a pointless endeavor, unless you have a porch garden going, and even then, it's probably not needed. If you live in a house, however, composting is an invaluable resource that gives you super-rich, water efficient, loose topsoil out of stuff you'd otherwise throw away. This will save you a considerable amount of money in the long run, as a mere 40 lb bag of compost can run from $5-25, and good fertilizer can cost $10-25 depending on where you live and shop. It will also provide a much richer nutrient soil than the bags you buy at the store. Whether you are planting something new, or simply refreshing the soil that an existing plant is already using, compost comes in extremely handy for anyone doing any sort of yardwork. It also helps reduce the amount of trash you produce each week, as well as decreasing the stench of your garbage. It keeps chemicals out of your garden, and is proof positive that you can feed your own food supply without the aid of store-bought goods.

THE BASICS:

Composting is really easy. I mean REALLY easy. All you need is an airy container, and vegetable matter to put in it. Placement plays a significant factor in how efficient your compost heap is at helping you out, but other than that, there's really not much thought put into it.

THE CONTAINER:

If you have the money, there's some real fancy compost bins you can buy. A recently favored one is basically something the size of an oil drum with a spit-handle on it that you can turn the whole thing with. Personally, I prefer scrap wood and a nail gun. After all, my goal was to save money, not find new ways to spend it.

Your composting process needs Oxygen to work, otherwise you end up with anaerobic bacteria, which produces sulphide gas or something, stinks, and retards the decomposition. However, it's really easy to get enough oxygen to your box, simply leave the "floor" of it open, make the sides out of something like pegboard (that fiber-board stuff with the evenly spaced grid of holes that you can put hooks in to hang stuff from), or space your side-boards each an inch or so apart. Loose biomass like grass, etc, won't fall out of the sides, because it's too fluffy, and later on, when it become compost, it tends to stick to the other compost, and not fall out the sides.

You'll want some sort of loose, water-impermeable top for it. I used a couple of rubber floor mats that we had laying around. It doesn't have to fit perfectly, your aim is simply to retard the water evaporation process. Water is the highway of life. The wetter your compost is, the more quickly and thoroughly it will decompose. However, you want to avoid over-soaking it because you don't want pools of water in it (which would help mosquitoes grow) and you don't want to wash your compost away either. The solution? a water impermeable top like a rubber mat catches water vapor and drips it back down onto the compost. The weight of the mat also slowly compacts the compost over time as well, which becomes more important as it fills.

Mistake - My very first compost heap was simply chicken-wire wrapped around 4 posts sticking in the ground, and some of the weed-blocking mesh lining the side. It made sense at the time, but what I quickly found out was that water evaporated through the mesh far too easily, and later on I realized weeds growing up through chicken-wire cannot be easily removed by hand or cut with the weed-eater.

PLACEMENT:

Most people make the mistake of putting the compost heap as far away from the house as possible. 2 problems with this I've learned over time. 1 is that compost heaps erode over time and if your drainage drains away from your yard (which it probably does) then you will lose a large portion of your soil, and leech a large amount of your nutrients through water runoff. The other problem with placing it so far away is the of hauling the fresh compost later on. 10-50 yards doesn't seem like much till you have to lug a wheel barrel full of soil over, and over, and over, and over.

The most efficient place for your compost heap depends on if you already have a garden, or if you plan to have one in the future. If you plan to have a garden in the future that ISN'T against the side of your house, then put it at the site of the future garden. That way your fresh compost soil is right there, ready to be used when it's planting season, and no hauling is needed. Plus the water runoff from the compost will fertilize the surrounding area nicely.

If you already have a garden, put your compost heap uphill from it, right next to it, if possible. The advantage here is very similar, water runoff from the compost heap will continue to fertilize your garden throughout the year, and the re-composting of your garden will be that much easier the next year because you won't have to haul very far. A third advantage of this is that if you plan to expand your garden, each successive compost heap you add is a nice patch of fresh, soft, yielding soil that you don't have to till.

CONTENTS:

As for the contents of your compost heap, it's real easy. Anything you look at, ask "Animal, Vegetable, or Mineral?" if the answer is "vegetable", go ahead and add it. Old fruits, potato salad, leftover choppings from fresh veg, stale tortillas and hamburger buns, uneaten salads, grass clippings, egg shells, tree leaves, stale cereal, etc, all are fine additions to your compost heap. But ALSO you can add the waste from your vacuum cleaner, the fuzzy stuff from your dryer's lint-catcher, paper towels, cotton rags and shirts, etc... all of those break down into easily composted stuff, and especially in the case of the vacuum cleaner bag, actually help by infusing your compost with all sorts of tiny microscopic critters looking for something good to eat.

Avoid salted stuff, as salt and plants don't get along well. Do not add meat and try to avoid dairy products. These do not break down as easily, stink, and attract larger vermin, like rats, cats, etc. Plain old veg won't attract anything larger than a mouse, and in 3 years of composting, I've only ever seen a mouse once. I've been told to avoid bush leaves (as opposed to tree leaves), as bush leaves are not digestible by worms, but I add them anyway as they help to mulch the compost with stuff with "water holding" matter. I've also noticed that wood does not break down well. So I'd avoid tree branches. Strip the leaves if you want, but leave the branches on the curb or burn them or something. Rose-stems I'm not sure about yet. They're practically wood, but are still -green- so perhaps are breakable. Crepe Myrtle, however, is basically the same as wood, so I'd avoid that.

That said, putting "indigestibles" such as woody stems or branches in your compost won't stop it from composting, it'll just make it more of a pain to turn, and be more work for you later on when you're trying to shovel or rake it, as they'll have to be removed. What would be a much wiser use of your tree branches is to burn them, and spread the ashes at the base of any food-crops or flowers, to help repel various pests.

MAINTENANCE:

The most obvious is that you have to keep your compost heap well-fed, and occasionally watered (remember, water is the highway of life). A fourth advantage of putting your compost heap besides an existing garden is that when you water your garden, you can just uncover the compost heap and let it catch the sprinkler/mister/etc water. Mine is watered along with all the vegetables, and it requires no extra water on our part because of this placement.

Turning the compost is recommended for the best results, but honestly, if your box is well ventilated, you won't have to do it very often. My previous compost heap was turned once every two to three weeks. To "turn" the heap, get anything that has a forked or hooked end (like a hoe or metal rake), and just jab it into the compost heap, move some stuff around here and there, and you're good. You don't have to stir it and homogenize it like sugar in tea, you just have to expose the buried bits to some more oxygen and water). After turning, I'd recommend watering the heap before recovering it, but this isn't absolutely needed.

Mr. Johnson, who runs a really huge garden, doesn't bother with turning or even a box. He circles his garden in railroad ties (those big long square-like log things people use in terraced yards) two-high, and piles stuff against them, and then covers it with dirt from the next space over. He never turns it, never "waters" it, and over the course of a year, has usually expanded his garden with thick, rich topsoil about a foot deep, and a couple of feed wide, all the way around. At the next planting season, he simply moves the railroad ties back outward, hoes it all even and spread out, and then plants his rows.

One more useful tip. Making a trip out to your heap every time you've got a piece of vegetable matter gets tiresome real quick. But you also don't want to keep a container of nasty veg-patter just sitting open in your kitchen all day. I solved this problem by putting a bucket out in the grass, just off the back porch. That way I can toss stuff in there, and every couple of days, dump it in the heap. It's a much shorter walk, turns 20 trips to the heap into 1, keeps the mess outside the house, off the porch, and critters don't mess with it because it's just rotten veg. The only ones who would care about it can't tip the bucket over easily. The only thing I've ever seen taken out of the bucket was a corn chip that made it about 3 inches from the bucket, and I think the dog did that.

Lastly, you don't have to keep all your compost for the year in one heap. The more you realize you can put in the compost, the more compost you end up making. Feel free to start a new heap once yours reaches a foot or two in depth and move the box over, just cover the old heap in dirt or something and maybe some mulch (dead leaves, for instance) to keep it from drying out too much.

SIDE NOTES:

After you've composted for a while, you'll start to understand why so many people who do it find it strangely fascinating in a way they can't really talk to neighbors about. There's a certain... awe... for lack of a better word, that goes along with watching this microcosm of life, an entire ecosystem, form around your compost heap, and the realization of where soil comes from. Just watching the layers of life taking place, and the breaking down of stuff into smaller components, and the realization that this is how soil is actually made. Previously, I always kind of just imagined soil as being the ultimate result of mountains breaking into smaller and smaller pieces...

I knew things decomposed, and kind of added to the general mess, sorta, in an abstract sort of way, and that they went somewhere. Likewise, I knew that plants drew nutrients from the soil, somehow, but never really associated it with much of anything. It wasn't until I watch as, day after day, that loaf of bread, bit of cabbage, paper towel, coffee grounds, etc., all become less and less recognizable as such, and get eaten and processed by bacteria, bugs, and things, and their waste or remains in turn, get processed, over and over in this tiny, relatively isolated little ecosystem, until a few weeks later you have...dirt. Really nice, thick, rich dirt, and then taking that soil, planting something in it, and watching the soil itself literally shrink and disappear as the plant grows and eventually, itself, contributes to the next compost heap.

It's very "Circle of Life" in a way that no Disney song or textbook can ever really convey. If you have kids, get them involved in the process. You'll probably get some "Ewww!" from them when they look at the bugs and such, but if they look at it every day or two, it will not only provide them with a useful skill, but a hands-on education in biology, and will probably help save them from a couple of common fears (like bugs). It also gets them involved in household maintenance, being a part of the yardwork early on, as well as teaching environmental stewardship and a fiscally sound method of generating plant food from stuff you'd otherwise throw away.

On a final note, composting, along with using those blue recycling bins, has reduced our trash output by 50-75%, and we're not even zealous about either.

I hope this helps. If anyone has any questions, I'd be happy to answer them as best I can.


[edit on 4/21/2008 by thelibra]

Another good post. Thank you.

Do you add compost to an existing garden, as in one with plants growing now, or do you only add it before you plant? If that makes sense....

Originally posted by Karlhungis
Do you add compost to an existing garden, as in one with plants growing now, or do you only add it before you plant? If that makes sense....

Great question! Either is actually a good idea. If you want to add it to an existing plant, I'd recommend scraping the mulch away from the base of the plant, if it's mulched. Then, using a fork, or claw, or small spade, break up the soil around the base of the plant, carefully, so as not to damage the roots or the trunk/stem of the plant. Then mix the compost in with the existing soil, leaving a final mound that's a bit higher than the average ground level. That way, when the soil settles, you aren't left with a depression around the base of the plant.

Then simply cover the mound with some mulch to help retain the moisture and retard weed growth.

reply to post by thelibra


Thank you for the response. And by mulch, we are just talking about simple bark mulch right?

Originally posted by Karlhungis
...by mulch, we are just talking about simple bark mulch right?

Well, actually, quite a number of things can be used as mulch:

I personally love Enviroguard, it's the best mulch I've ever used, made of recycled newspaper, it doesn't float on water, doesn't blow away (and we get some really high winds in Texas), doesn't have any chemicals in it, takes years to break down (ie before it needs to be replaced) and retains its color beautifully for years (the two colors I've seen so far are red and brown). Unfortunately, it's also the most expensive mulch I've run into at $12/bag. Now, you can cover a lot of ground with one bag, since you only need to use about 1/4-1/2 the mulch to cover the same area as you'd need from wood-bark, and you don't have to replace it nearly as often, because it takes so long to break down. So it's a better investment in the long run, but a larger expense in the short run. Anyway, that's the high-end of mulch.

The cheaper $3/bag mulch for shredded wood will do okay, but tends to lose its color encourages plant lice, slugs, and snails, and also will need to be replaced on a yearly basis, and since it floats, a heavy rain will either wash it away if not walled in, or displace it all to the lowest point if walled in.

If you want completely free mulch, and don't mind the extra work involved, simply use the bag attachment on your mower, and empty it directly into the area that needs to be mulched. Grass breaks down really quickly, floats and blows away easily, so you'll be replacing it constantly. But it is free and also will provide nutrients as is mulches. Since I'm in Texas, under harsh, direct sunlight, I use the mulcher on the mower, and let the cut grass fall back into the yard, so it shields the roots of the growing grass.

You can also make really great mulch out of wood ashes, used coffee grounds, and eggshells. The combination of those three, mixed up, will provide not only a great mulch, but also provides an incredible barrier to many, many pests. But since the only way you'll end up with those things in any large quantity is to own a bed and breakfast, it's really for more of a special-use sort of thing. I'm seriously considering though canvassing the local restaurants to see if I can have their used grounds and eggshells, and then just burning my own branches to make the ash.