Composting in a Tumbler, Nothing is Happening
Question
March 17, 2013
My wife and I bought a Lifetime Dual Compost Tumbler at Christmas. There are two 50 gallon bins mounted side by side that have an air pipe going through the middle of them and they rotate. We had been saving "brown" and "green" material for the last year so we filled both containers on 23 Jan 13. Since that date, it seems like nothing is happening in both bins. The material looks the same as it did on 23 Jan. We used a ratio of 20 parts "brown" to 1 part "green". We turn them every couple days. It seems like the material is very dry so we occasionally add some water. We have the composter on the south side of the house where it gets direct sunlight (i.e., heat) all day long. We were really excited about composting but our enthusiasm is deteriorating as each day passes and it seems like nothing is happening. What are we doing wrong? Any/all help would be greatly appreciated.
Answer(s)
Answer by WR: Hi Jeff, it could be that by the time you put the materials in the tumbler, the "greens" had turned "brown". Greens need to be pretty fresh. I think if you can find some fresh greens to add this will help. Perhaps you can visit your closest coffee shop a few times and ask for their leftover coffee grounds. (The Starbucks near me is nice about giving me theirs.) It might take quite a lot to get the process going. Certainly add all the kitchen scraps you can get your hands on. Here's a list of greens and browns.
You are correct in adding water. It needs to be moist, about like a wrung-out sponge.
Heat from the sun doesn't really help. You'd probably do better to put the composter in the shade, at least this time of year as it starts to warm up. This will keep it from drying out so quickly. I don't think you'll be able to get your compost to heat up inside your tumbler. To get a hot compost pile you need a very large pile...about 3 feet by 3 feet by 3 feet. The heat inside such a pile is not from the sun but from bacterial action inside the pile and from the insulating properties of such a big pile. So, what you are making is "cold compost". That is fine. It's perfectly good stuff but won't turn to compost as fast. (If there is a lot of weed seed or perennial weeds such as bind weed or bermuda grass in the compost, that might not totally decompose in a cold compost.) With a tumbler, since it's not going to get hot, you'd be better off to just add materials as you collect them, trying to keep a decent green/brown balance. Doesn't have to be exact. If it's slimy and smelly, add more browns. If it's just sitting there doing nothing, add more greens. In either case, keep stirring and keep moist but not over-moist. Don't worry if it is temporarily out of balance. You can always get it back into balance over time. We offer free composting classes here in Albuquerque. If you live here or nearby you might consider taking one of them. Hope this helps. Let us know how it goes.
Hope you won't be discouraged. Once you get the right balance, I think you'll find it's really fun and easy and rewarding to compost.
Answer by JZ: Here is my opinion:
Where do you live? Composting in the desert requires that we moderate air flow in a bin in order to decrease evaporation. You may have to tape over some of the holes in your tumbler.
If you are intending to do a "hot" composting batch method, then you need to increase the nitrogen in your mix. You could start with a mix that is 50%: 50% C:N or 60:40 or minimally 75:25. You should consider adding bulking materials: sticks, twigs, pine cones, corn cobs, corn stalk. Bulking will decrease compaction in the total mix in the tumbler as you need to maintain 50% moisture throughout the composting process.
See our recommendations for desert composting.
With a little bit of "tweaking" and practice your composting operation will be fine.
You are welcome to attend any of our free classes.