By MICHAEL J. McGROARTY
Published: Tuesday, March 31, 2009 | 2:59 PM
Having an ample supply of good rich compost is the gardeners dream. It has many uses, and all of those uses will result in nicer plants. However, composting can be time consuming and hard work. I place a reasonable value on my time, so spending hours and hours turning compost piles doesn’t qualify as a worthwhile exercise, at least in my book. Nonetheless, I do compost, but I do so on my terms.
I built two composting bins. Each bin is five feet wide, five feet deep, and four feet high. I built the bins by sinking 4” by 4” posts in the ground for the corners, and then nailed 2 by 4’s and 1 by 4’s, alternating on the sides. I left 2” gaps between the boards for air circulation. The 2 by 4’s are rigid enough to keep the sides from bowing out, and in between each 2 by 4 I used 1 by 4’s to save a little money. The bins are only 3 sided, I left the front of the bins open so they can be filled and emptied easily.
I started by filling just one of the bins. I put grass clippings, dried leaves, and shrub clippings in the bins. I try not to put more than 6” of each material on a layer. You don’t want 24” of grass clippings in the bin, you should alternate layers of green and brown material. If necessary, keep a few bags of dry leaves around so you can alternate layers of brown waste and green waste. When we root cuttings we use coarse sand in the flats, so when it’s time to pull the rooted cuttings out of the flats, the old sand goes on the compost pile.
In our little backyard nursery we also have some plants in containers that do not survive. Rather than pulling the dead plant and the weeds out of the container, and then dumping the potting soil back on the soil pile, we just dump the whole container in the compost bin, this adds more brown material to the mix, and is a lot easier than separating the soil and the weeds.
Once the bin is full, the rules of composting say that you should turn the material in the bin every few weeks. There is no way that I have time to do that, so this is what I do. I pack as much material in the bin as I can, before I start filling the second bin. I pile the material as high as I possibly can, and even let it spill out in front of the bin. Then I cover all the fresh material with mulch or potting soil, whatever brown material I can find. Then when I’m out working in the garden I set a small sprinkler on top of the pile and turn it on very low, so a small spray of water runs on the material. Since I have a good water well, this doesn’t cost me anything, so I let it run for at least two hours as often as I can. This keeps the material damp, and the moisture will cause the pile to heat up, which is what makes the composting action take place.
Once I have the first bin completely full, I start using the second bin. As the material in the first bin starts to break down, it will settle, and the bin is no longer heaped up, so I just keep shoveling the material that I piled in front of the bin, up on top of the pile, until all the material is either in the bin, or piled on top of the heap. Then I just leave it alone, except to water it once in a while. The watering isn’t necessary, it just speeds the process.
Because I don’t turn the pile, I can’t expect all of the material to rot completely. The material in the center is going to break down more than the material on the edges, but most of it does breakdown quite well.
The next step works great for me because I’ve got a small nursery, so I keep a pile of potting soil on hand at all times. But you can really do the same thing by just buying two or three yards of shredded mulch to get started, and piling it up near your compost bins. If you do this, you will always have a supply of good compost to work with.
Shredded bark, left in a pile will eventually breakdown and become great compost. The potting soil that I use is about 80% rotted bark. I make potting soil by purchasing fine textured, and dark hardwood bark mulch, and I just put it in a pile and let it rot. The secret is to keep the pile low and flat, so that it does not shed the rain water away, you want the mulch to stay as wet as possible, this will cause it to breakdown fairly quick.
So I keep a pile of rotted bark mulch near my compost bins. When both bins are completely full, I empty the bin containing the oldest material by piling it on top of my rotted bark mulch. I make sure the pile of rotted mulch is wide and flat on top so that when I put the material from the compost bin on top of the pile, the compost material is only 5 to 10 inches thick. My mulch pile might be 12’ wide, but it may only be 24 to 30 inches high. Once I have all the compost on top of the pile, then I go around the edge of the pile with a shovel, and take some of the material from the edges of the pile and toss it up on top of the pile, covering the compost with at least 6” of rotted bark. This will cause the compost material to decompose the rest of the way.
Once you get this system started, you never want to use all of the material in the pile. Always keep at least 2 to 3 cubic yards on hand so you’ve got something to mix with your compost. If you use a lot of compost material like I do, then you should buy more material and add to your pile in the late summer or fall, once you are done using it for the season. Around here many of the supply companies sell a compost material that is already broken down quite well. This is what I buy to add to my stock pile. But I try to make sure that I have at least 3 yards of old material on hand, then I’ll add another 3 yards of fresh material to that. Then in the spring I’ll empty one of the compost bins and add the compost to the top of the pile.
The pile of usable compost will be layers of material, some more composted than others. Kind of like a sandwich. So what I do is chip off a section of the pile from the edge, spread it out on the ground so it’s only about 8” deep, then run over it with my small rototiller. This mixes it together perfectly, and I shovel it onto the potting bench.
Having a pile of rotted compost near your compost bins is great because if you have a lot of leaves or grass clippings, you can throw some rotted compost in the bin in order to maintain that layered effect that is necessary in order for the composting process to work well.
Sure this process is a little work, but it sure is nice to have a place to get rid of organic waste anytime I like. Then down the road when I have beautiful compost to add to my potting soil, I am grateful to have done the right thing earlier, and I know that I have wasted nothing.
Michael J. McGroarty is the author of this article. Visit his most interesting website, http://www.freeplants.com and sign up for his excellent gardening newsletter, and grab a FREE copy of his E-book, “Easy Plant Propagation.”