Testing Compost Tumblers

MOTHER EARTH NEWS shares the results of testing compost tumblers on the market, including tumbler styles, feature pros and cons, operating factors and test results.

MOTHER EARTH NEWS spends some time testing compost tumblers comparing the end product to that of a compost bin or pile.

MOTHER EARTH NEWS spends some time testing compost tumblers comparing the end product to that of a compost bin or pile.


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MOTHER EARTH NEWS has results from testing compost tumblers on the market and comparing them to compost created in compost bins or piles.

Testing Compost Tumblers

You've seen the ads: "Now you can have dark, rich compost in just a few weeks!" What an appealing message. Whether you grow flowers, vegetables, herbs or houseplants, compost is "black gold" in the garden. We never have enough of it, and can't make it fast enough. Compost tumblers, the ads say, can give us a steady supply every couple of weeks. Designed so you can crank, turn or roll the container to turn and aerate the compost, tumblers come in several sizes.

Before you run out and buy one, however, be aware that those headlines are advertising hyperbole at best. In our tests, tumblers did not produce finished compost any faster than a well-managed compost bin or open pile.

To be sure, the ingredients appear to be composting faster because you are likely to turn the contents more often in a tumbler, thus introducing air — one of the four vital ingredients (the others being nitrogen, carbon and water) — that is necessary to turn vegetable matter into compost. But if you build an open pile the same size as a tumbler's capacity, use the same ingredients in both and turn the open pile whenever you rotate the tumbler, they will produce compost in the same general time frame. So, why should you buy a compost tumbler?

Last summer we conducted a field test of various compost tumblers versus open compost piles. Although most of us at MOTHER use cold composting methods (substituting time for the work of maintaining a hot pile), we ran a hot pile as a control.

Under our environmental conditions, both the open (hot) pile control and the tumblers yielded rich, finished compost in about 10 weeks — a far cry from the 14 days some of the manufacturers claim. The tumblers were certainly easier to use than turning an open pile with a pitchfork, but they did not appreciably increase the speed of production when compared to a properly managed open pile. Ease of turning is probably the main benefit tumblers offer, but as you will see below, some are easier to turn than others.

Although the decomposition time is not increased, compost tumblers do have advantages in addition to ease of turning. By and large, they are clean, neat, unobtrusive, pest-resistant and odor-free. Because of this, tumblers often can be used in urban and suburban areas, where local laws or restrictive covenants may prohibit open compost piles.

One pleasant surprise during the testing, in what turned out to be a drought year, was that the enclosed tumblers retained moisture better than the open pile, which had to be watered frequently.

Compost Tumbler Styles

Compost tumblers fall into four general categories based on their construction:

Crank-operated drums. A horizontally mounted drum rests on a raised framework. A crank assembly lets you turn the drum easily, while the internal baffles help mix the materials, adding air.

Because the drums are raised relatively high, emptying them is simple. Merely push a wheelbarrow under the drum, position the door and open it. Compost pours directly into the wheelbarrow.

This style of tumbler tends to cost about twice as much as other styles. But, as with anything else, you get what you pay for. In this case, you trade money for ease of operation.

The Mantis ComposTwin and the ComposTumbler are examples of this design; the former has a double drum and the latter has a single drum (available in two sizes).

Center-axle drums. A vertically mounted drum rotates around a central, horizontal axle supported by a wood, metal or PVC frame. Operation is generally easy, particularly with the models that have doors on both ends. The central axle acts to break up and mix the materials. Most of these tumblers are mounted low to the ground, however, so emptying them can be a chore unless you have a low-boy wheelbarrow that happens to fit under them.

The Urban Compost Tumbler (UCT) and the Tumbleweed are this type.

Base rolling drums. A horizontally configured drum rolls on a ground-level base. Some of them actually have rollers, while others have molded rounded points to suspend the drum and let it rotate. Obviously, the tumblers with rollers are easier to turn. To help make rotating easier, several of this style have steps molded into the body, so you can use your feet and legs to turn them, thus theoretically easing back strain.

Because the base rolling tumblers virtually sit on the ground, emptying them can be awkward. You have to shovel the compost out — through relatively small openings — rather than pouring it.

Typical of this design are the Envirocycle, the Step-down Composter and the EZ Composter. 

Roll-Around Sphere Compost Tumblers. These are giant molded angular balls that you fill with composting material and then roll around your yard. The idea is initially intriguing; in practice, however, they tend to he the most awkward to use and the most difficult to empty.

Roll-around composters are not really round, but are faceted like a geodesic dome. As a result, they only roll on what would be their equator. And, instead of rolling like a snowball, they swing to the left or right in sharp arcs. The heavier they are loaded, the less control you have.

The Bio Orb and the Large Batch Composter are examples of this style.

Compost Tumbler Features: Pros and Cons

Once you have decided which kind of tumbler you want, look at the specific features of each. It's the little things that can make or break a design.

For instance, compare the Envirocycle to the EZ Composter. The former has a hinged door. The latter has a round hatch with finely threaded screws. As a result, loading and unloading the Envirocycle is considerably easier than loading and unloading the EZ Composter, which has a hatch that is difficult to screw down even when the unit is new, let alone after dirt and debris clog the threads.

Among center-axle types, some, such as the Tumbleweed, open at both ends, while others, such as the Urban compost Tumbler, open only atone end. Having openings on both ends makes loading and unloading simpler. However, the extra air flow of the UCT's patented core-aeration system, which precludes having both ends open, might he worth the trade-off.

Capacity also can be an issue. Many models come in more than one size. At first blush, the larger size seems to make sense because it produces more compost in the same amount of time as a smaller one. But the larger one also might he heavier and more difficult to operate.

There's another aspect of capacity to consider. Composting speed is a function of the last items to he added. That is, you won't get a full load of compost unless you've put in a full load of organic material. This doesn't mean you can't add material a little at a tune. What it does mean, however, is that "time to completion" is measured from the last of those small additions.

Because of this, you may want to have more than one unit. Start by completely filling one with a mixture of brown and green compost material. Examples of brown material are fine mood chips, brown weeds, straw, leaves and kitchen scraps; examples of green material are grass clippings, green garden cast-offs and manure.

While that batch "cooks," you can slowly fill another unit.

This is the idea behind the ComposTwin: You can have one bin filled and composting while you are adding fresh ingredients to the second bin.

Compost Tumbler Operating Factor

Whichever unit you choose, you should be aware of certain operational factors:

1) Ignore recommendations to use compost accelerators. About half the manufacturers still recommend this practice, yet study after study has shown that such additives have no appreciable effect on the composting process.

2) The proportion of green material to brown is more crucial in a closed tumbler than in an open pile. If you don't add at least 40 percent browns, you'll end up with a slimy, smelly mess instead of compost.

If nothing else is available, keep a bag of leaves or a bale of straw handy and use it as necessary to maintain the balance. In most cases where users have reported poor results, it turns out they have been adding only grass clippings and kitchen scraps to the unit.

3) All tumblers are pest-proof to rodents, dogs and other animals — not to insects. When you open a tumbler, be prepared for a cloud of gnats to emerge. The fact is, these same gnats hover over open compost piles, but you are less aware of them because you don't encounter them in mass.

4) Monitor the moisture content. Tumblers retain moisture letter than open piles, so you don't need to add much. Usually, grass clippings alone provide more than enough moisture. Your working pile should feel like a clamp sponge.

If it's wetter than that, leave the door open awhile so it can dry out. Occasionally you may have to add a small amount of water. If so, add no more than a cup at a time, and be sure to tumble the contents after each addition.

5) Air is crucial to the composting process. Periodically check to ensure the vents in your composter haven't been clogged by organic material. If you think the mix isn't getting enough air, rotate tile tumblers more frequently.

Compost Tumbler Sources

Mantis. 800-366-6268;

Envirocycle Systems. 514-767-7770;

Eons Down Under Wares. 877-886-2532;

Urban Compost Tumbler:
D&P Industries. 877-546-4400;

EZ Composter:
Spruce Creek. 800-940-0187;

Planet Natural. 800-289-6656;

ComposTumbler. 800-880-2345;

6/1/2016 1:40:45 AM

Great article.Thanks for sharing.

3/23/2014 9:13:03 AM

We have skunks getting into our compost bin, no matter what we do to fortify the yard, thinking the tumbler would be the way to go as they are attracted to the compost pile.

gayle and paul naiman
5/6/2012 3:56:48 PM

I just purchased a Lifetime 80 gallon compost tumbler #60058. Very unhappy with this purchase for the following reasons: Broken fastener packages within a cheap cardboard container, with many fasteners missing. Assembly instructions misleading and frankly inaccurate in their diagrams. All metal fasteners are just flash cadmium plated. My experience is that these will rust within a year of outdoor exposure. My analysis: This is a cheaply made Communist Chinese product pandering to people interested in backyard gardening. DO NOT BUY THIS PRODUCT.

john haendiges
5/10/2011 10:19:56 AM

I recently purchased the large ComposTumbler at a savings of nearly $80 via Amazon.com, and I have to report being pretty pleased with it. Despite some early setbacks caused by the torrential rains we've had recently in southern Indiana causing excessive moisture inside the drum, it has so far generated a substantial volume of finished product in nearly the advertised time. It has also produced a copious quantity of tea, which drains quite handily into the plastic garden cart I park beneath it. When positioned correctly the tea drains off all by itself, and the tumbler receives a more than adequate supply of oxygen. To the reader whose metal sides rusted away in just a few years may I suggest that perhaps your maintenence of the tumbler was at fault, not the galvanized metal itself. Rinsing the drum with clean water between cycles is critical. Coating the inside of the drum with vegetable oil will extend the life of the panels for many years, just be sure to inspect and thoroughly clean out particles from the crevices, and air dry the panels completely before oiling. A light coating is sufficient.

6/1/2010 7:24:31 PM

I live in town, although my neighbors are not that close. Our compost lives in a three by five wooden box we built from scraps. It sits in a partially shaded area and has a wooden slat door. It smells a bit, but not bad. It's kind of messy I guess, but this is gardening, kids. Our way works and my organic garden is very happy.

7/27/2009 8:16:32 PM

I'd like to start composting but have concerns about the temperature issues. I live in the Midwest with LOW winter temps, and also the only place I have to put a compost bin in my yard is in full shade. Will this affect my results? I don't really care how long it takes to mature into compost.

steve steiner_1
7/17/2009 6:48:10 PM

I bought a Compost Tumbler, the original big one, for about $400. After a few years the galvanized sides started to rot out. I called to ask about new sides. They cost the company maybe 30 bucks, tops. Replacing them costs $275.00. Make something yourself, even chicken wire held up with metal posts, leave the front side open. Works great, no worries, ten bucks.

7/10/2009 3:36:29 PM

The notation about the gnats is helpful - I'm glad to know that my cloud of gnats is normal. I have to agree with Dennis - it is possible to speed up composting if done properly. I own a Compact ComposTumbler from http://www.compostumbler.com. It's a smaller version of the model reviewed in this article. As Dennis mentioned, to make compost in about 2 weeks, I have to chop my food scraps into small pieces and shred my leaves. I also make sure that I have the right proportion of "green" to "brown" material and turn the tumbler daily, checking the temp and adjusting the moisture as needed. The tumbler makes turning the compost very easy, but it is a process that requires some time and effort and I don't have to wait all summer for my compost!

6/5/2009 1:40:28 PM

It saddens me that I'm no longer living the Mother Earth life. Have somehow put myself in a new subdivision with a tiny yard surrounded by a privacy fence (an abomination, a blight on our society). But the wife loves it, so I guess I'm happy. Found this site looking for a composter that would work in our small yard. The review started well, but never seemed to finish with a detailed comparison of composters. For you Mother Earthers still enjoying living closer to the land, may I offer my own site on composting, with the wish I could still be with you: http://www.stevenkohn.net/compost/

erica chapin_1
5/14/2009 7:44:35 PM

Has anyone tried the Jora composter. It is metal vs plastic and seems like it will last longer. Thanks!

4/25/2009 9:43:42 AM

I made a cheap and effective composter with a 50 gallon plastic barrel that comes with a lid and ring to seal it. I bought a barrel from a local vinegar factory for $2 and made 2 inch burr holes all around it. I put the compost in it, seal it up and just roll it over every few days. I haven't really had problems with the compost falling out of the holes and if a little of it does I just scoop it up and put it around the plants in my garden. You need to make sure it doesn't get more than 3/4 full or the compost won't tumble well.

3/30/2009 9:05:54 AM

I have a compost Tumbler for two years and have not been happy with the performance in the sense that it takes so long to decompose and also the messiness of the whole project. I tend to disagree with the author/s that composting cannot be expediated. The compost needs Oxygen(air), water, temperature (steady at 95-100degrees F) and most importantly---Small particle size (make sure that all the stuff you put into the compost is as fine as you can possibly make it, without going overboard). If these factors are taken care of, alongwith periodic tumbling, the compost pile should be ready in less time than the manufacturers claim. Also, adding a compost starter, though not essential, would help because it contains the microbes which breakdown the "vegetation" into compost. It doesn't necessarily have to be the package that they are trying to sell you----- just some moist earth or some previously composted material will do. Another factor that can greatly expediate the process is controlling the pH (acidity or basicity) of the mix. I'm working on collecting the "tea" on a regular basis. All input is welcome. Dennis Balgi

peter richeson
3/22/2009 4:49:14 AM

I have the Urban Compost tumbler and hate it. To start with it is very hard to turn if it is over 1/4 full. After about 6 mo the lid got harder and harder to put on. The aerating tubes that run through it make it very hard to get the compost out and it is not high enough to just dump. I just ordered a different style. I will never own a compost tumbler like the urban compost tumbler again.

peter richeson
3/21/2009 6:35:32 PM

Hi all

3/17/2009 11:51:17 PM

I use the urban compost tumbler as well. I bought it from http://www.organic-composter.com . Different from the other sites that are listed but probably the same product. I have had little success with compost piles previously and always felt that compost bins were just a pile with a plastic box on top. My wife bought the urban compost tumbler last year and it worked just as advertised.

2/2/2009 6:30:52 PM

I have built my own compost tumbler with a center aeration tube. It makes compost in aroung two-three wks if I tumble it every day. The first worked so well, I built another so I could scarf materials from my neighbors who don't garden. Adding cow manure tea helps if it gets dry. I tried the horizontal barrel type and didn't like it, so I went to the screw-on lid plastic barrel vertical tumble style and I love it.

7/31/2008 1:27:10 PM

well I found a number of composters, but especialy one that looks great: the autoflow compost tumblers. I am going to purchase one right now from Eartheasy.com with a 10% off coupon, EARTH, so wish me luck! I think this is the url: http://eartheasy.com/shop/composting.htm

2/6/2008 11:27:27 AM

ok, I was just getting into the review on tumbler composters, when it repeated the top section of the review and never actually finished the review! is there a completed version of the review out? thank you sandy

12/8/2007 9:45:00 PM

I have the urban compost Tumbler and will say that it is easy to turn compost it didnt work as fast as advertised and unloading is not easy.

11/27/2007 3:22:35 PM

I got my Urban Compost Tumbler here: http://www.organic-compost-tumbler.com Not the website you listed, but its the same product. It works really good. In summer when heated up it literally can steam. To empty I use a snow sled to catch it all.