Some gardeners tend to hide their bin, but for me it's a source of pride.
Composting at home is easy if you remember these 4 factors when building your DIY compost pile. Of course, I'm using organic composting methods here, so no chemicals.
1. Compost Aeration
Oxygen is important because we’re doing aerobic garden composting. There are two basic methods to ensure there’s enough air, and you can use either or both.
The first is to put a layer of brush, branches and sticks on the ground under the pile that is at least a few inches high. The second method is to turn the pile over once in a while. For the fastest decomposition, this is done whenever the pile starts to cool down from it’s hot phase, usually every 3-7 days.
Even turning a compost pile once each season is helpful. In fact, when I’m not in a hurry, this is what I do when composting at home because while an unturned or little-turned pile takes longer to finish, it retains more nutrients.
The fastest way to get it done, however, is to turn it regularly. A “hot” compost pile can be largely done in 2-4 weeks. Most weed seeds and pathogens can be killed in this time. But a cool, slow garden composting process has big advantages, too. Not only does it retain many more nutrients, but research shows it’s more able to suppress disease, probably because more beneficial microbes survive the composting process, especially fungi.
We can also allow the compost pile to go through a maturation phase, where it’s already looking like finished compost, but sits for another perhaps 6 weeks at a cooler temperature allowing many microbes to multiply. This curing time is vital when composting at home to make the best compost.
2. Compost Moisture
Your DIY compost pile should be moist like a wrung-out sponge. This means when you take a fist full and squeeze it, it should feel wet but not drip water. This is somewhere between 30% and 70% moisture, with 50%-60% generally considered ideal.
If the compost is too moist, it can turn anaerobic and promote the wrong microbes, as well as leach a lot of nutrients. If it’s not moist enough, decomposition will be very slow, but this is a better problem than too much moisture, which takes more effort to fix.
If the compost pile gets too moist or if it starts to smell bad, you can take it apart, air it out, and then add more carbon materials when you put it back together. If it gets too dry, water it and perhaps apply more nitrogen materials. You may need to take it apart here, too, in order to get it sufficiently wet.
3. Compost Temperature
Different studies have come up with different ideal temperatures when composting at home, but it’s generally agreed that 130-150F for several days is adequate for organic composting to kill weed seeds and pathogens. If you’re judging with your hand, it should be too hot in the pile to keep your hand there for long. Still, significant reductions in pathogens have happened when the compost pile never went above 104F.
To get the higher temperature, the compost pile should be at least 3 by 3 by 3 feet as a bare minimum, and as much as 5 by 5 by 5 (although some people go as wide as 10 feet).
For the most part, the more frequently a compost pile is turned, the hotter it tends to get and the hotter it stays, although the most important part of reaching high temperatures is the right amount of moisture, proper pile size, and balanced carbon to nitrogen ratio.
4. Compost Carbon To Nitrogen Ratio
When composting at home, if your pile has too much nitrogen, it may go anaerobic, create bad compost and smell awful. If the pile doesn’t heat up, you may need to add more nitrogen materials.
The ideal carbon to nitrogen ratio of a new compost pile is somewhere between 25:1 and 30:1, by weight, not volume. The way to get this ratio is to use between 2 and 4 times as many 'carbon' materials as 'nitrogen' materials (update: these days I use more like equal parts carbon materials and nitrogen materials). By the end of the garden composting process, the ratio in the pile goes down to somewhere around 10:1 because carbon is released as carbon dioxide.
Composting At Home Summary
Remember those 4 factors when composting at home and you will be on your way to mastering a beautiful organic composting process.
Any questions about these 4 topics? Do you have any other interesting DIY compost tips you use when composting at home?
Let me know below.