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Internet #202224250

Model #Sun-Mar 400

100 gal. Garden Composter

How to Get It

Product Overview

The Sun-Mar 100-Gallon Garden Composter is constructed of UV stabilized, 100% recyclable polyethylene. Featuring Sun-Mar's double-drum AutoFlow design, the composter automatically discharges compost out the output port. Compost such as kitchen scraps and garden materials go in at the top and move along the outer drum and through the inner drum as the drum rotates.
  • Holds 100 gal. of kitchen scraps and garden materials
  • Polyethylene construction is 100% recyclable
  • Double-drum AutoFlow design works as the drum rotates for quick operation
  • Odorless and pest-proof to provide hassle-free operation
  • UV stabilized for a long life
  • Easy loading and turning for convenience
  • Compost discharges automatically from the output port to help prevent waiting for batches to finish



Assembled Depth (in.)28 inAssembled Height (in.)35 in
Assembled Width (in.)47 inProduct Depth (in.)28
Product Height (in.)35Product Width (in.)47 in


Assembly RequiredYesCapacity (cu. ft.) - Total100
Capacity (gallons)100Color FamilyGreen
Composter TypeTumblerCoveredYes
Indoor/OutdoorOutdoorLandscape Supply TypeComposter
Low OdorYesOdorlessYes
Product Weight (lb.)80Returnable90-Day

Questions & Answers

Typical questions asked about products:

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Customer Reviews

  • 3.5
    out of 12 reviews
  • 70%recommend this product
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Showing 1-10 of 12 reviews
1 Star Review
Rating provided by a verified purchaser
  • Verified Purchase
Poor long-term durability
I've owned this product for two years and it's finally kicked the proverbial bucket. It does compost quickly, there are quite a few design flaws. First and foremost is the gear and handle. 1) The plastic clips on the base are not sufficient to hold the handle in place when the composter starts to get heavy, so the handle and gear pops out when trying to rotate the drum. 2) The plastic end cap that holds the drum in place on the gear-side of the unit is not sufficient to hold the weight of the drum, and will eventually break (like mine just did) 3) The base eventually stretches and will not support the drum as it rotates, and the drum will fall out of the base (like mine just did). Eventually it will stretch out so far that the drum will not stay in the base, even when reinstalled. Save your money.
    The compostter. Was very very easy to assemble. And very...
    The compostter. Was very very easy to assemble. And very sturdy. A great item. day ed
    • Verified Purchase
    We like the composter, but are having problems with it. The directions are in a small print, whi...
    We like the composter, but are having problems with it. The directions are in a small print, which we can read. But the pictures with directions are fuzzy and unreadable. We are having problems with the handle staying on (which we cannot read because of the picture with directions is unreadable). It is frustrating, but we are trying to get it to work.
    • Verified Purchase
    2 found this review helpful
    Great product
    Would be 5 stars but I haven't had it long enough to really know. Very nice product, fit and finish is great. Some reviews complain about difficult assembly, but I had mine out of the box and fully assembled in minutes. Still working on my first batch but it really seems to be coming along nice. The center chamber tends to fill with dry, uncomposted material during the first batch but it's easy enough to run it back through. Be careful with the crank!! if you let go or slip off the handle at the wrong time it will give you a good 3 smacks before you know what's happening.
      • Recommended
      6 found this review helpful
      Great idea Horrible product
      I have had 3 of these composters due to warranty replacements. They work wonderfully for 3-6 months and then fall apart when the center seperates and it falls out of the cradle. I have tried 2 all-thread rods through the side and a bolt in the back to hold the center drum in and they still fail. Customer service has been great but what a headache... save your money
        7 found this review helpful
        Would have gotten 5 stars, but.....
        The composter itself is well made & so far seems to work well (only have had it about 2 weeks). My only complaint is that the website claims you can assemble it in 5 minutes & it took my husband & I over 2.5 hours. Neither of us are particularly 'handy' but we're both intelligent people (engineer & optician) but the instructions to put it together require a bit of interpretation & were a bit out of order. Now that it is (finally) assembled, we've got it in the backyard & have no complaints. The opening to put your materials in is sufficient & once everything is inside, just close the door & give it a spin. The handle makes it very easy to turn the drum - just be careful - if the load hasn't shifted to the bottom completely the handle tends to spin around until the drum centers itself - I've been whacked by the handle once so learned that from personal experience. Now we're just waiting for some compost. The manual gave a wait time of 6 weeks, but we're just heading into winter now, so I imagine it won't be until 6 weeks after spring arrives that we see the results.
          • Recommended
          We just bought it so I don't have a ton of experience with it. The assembly itself is simple but the instructions make it confusing and one of the parts broke when we tried to put it together - they give you a back up though so they must realize that this part is hard to put on. It is easy to use and a basic composting guide is included to help you get started. I used to use a worm composter but seperating the worms from the compost was time consuming esspecially as we started producing more food and garden waste. This seems to be much simplar.
            • Recommended
            Garden composter
            I have recently purchased the Sun-Mar 400 garden composter. I have never had a composter before and did a a bit of research before selecting this one. I was easy to assemble and appears to be well built (should last for years). I placed it next to our garden and have started filling it with grass clippings and kitchen waste. I'm sure it will likely take a while to figure out how to compost but this unit was definetly a good choice.
              • Recommended
              Great composter
              I am glad that Home Depot delivered that big composter to my house as it wouldn't have fitted in my small car. Was very pleased with the speed of the delivery and friendly service. Product is solid and easy to assemble. Can't wait to see the results in a few weeks.
                • Recommended
                Showing 1-10 of 12 reviews