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Best and worst compost bins
Using a compost bin is the most effective way of managing the composting process, so consult our expert tests to see which one to buy
The bin you use for composting can make a world of difference to the speed and success of the process. Our latest expert tests have uncovered the best and worst for the job.
Composting is a great way to recycle garden and kitchen waste to make soil improver that you can use as a mulch.
On a mission to find compost bins that are easy to use and efficient, we tested 12 different models. Included in our rigorous tests were popular compost bins from big-name brands including Eco King, Grange and Thermo-Star.
Learn how to make compost for use in your garden
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Best compost bins
To identify the best compost bins on the market, we tested a selection of bins at different price points. There was a big difference between our top and lowest-performing compost bins.
Scoring an impressive overall rating of 79%, the best compost bin scored five stars for assembly, composting efficiency and yield.
But it was a very different story for our lowest-ranking bin. Scoring just 41% for overall rating, you'd be disappointed if you paid more than £100 for this particular model.
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| Compost bin | Price | Overall rating | Size (litres) | Assembly | Convenience: filling | Convenience: turning or stirring | Convenience: removing compost | Composting efficiency | Yield of good-quality compost |
|---|---|---|---|---|---|---|---|---|---|
| Botanico Composter | Friendly Fungi: £35 | ||||||||
| Eco King Composter Bin | SQUIRREL_TEXT_50017121 | ||||||||
| Ecomax Black Compost Bin | SQUIRREL_TEXT_50021020 | ||||||||
| Forest Slot Down Compost Bin | SQUIRREL_TEXT_50021007 | ||||||||
| Grange Large Composter | Fencing Essentials: £39 | ||||||||
| Green Johanna | SQUIRREL_TEXT_50017123 | ||||||||
| Hotbin 200L | Dobies: £255 |
The more stars the better. Rating ignores price and is based on: composting efficiency 30%; convenience of filling 20%; yield of good-quality compost 20%; removing 15%; turning or stirring 10%; assembly 5%. Composting efficiency scores comprised of average temperature of compost combined with the rate of settling and rotting.
How we test compost bins
We chose compost bins for the trial that represented the most common types available to buy.
We used three bins of each product and arranged them in three separate blocks, so none of the same types of bins were located near each other.
To fill the bins, we collected soft green and brown material and mixed it thoroughly in 50:50 proportions.
Each bin was filled to half its capacity in April of the first year, then every month was refilled with enough material to comprise a quarter of its capacity. Filling stopped in September of the first year, resumed in April of the second year and the trial ended at the end of July in the second year.
The contents were turned (or stirred where the bins weren’t easily emptied) twice in the first year in July and September, and once in the second year in late June, and the compost was watered if it dried out. Assessments of how much the compost had settled and started to rot and a temperature check were carried out every two months.
Ready to start composting? See our advice on how to make compost.
What are the benefits of using a compost bin?
Composting is a natural recycling process that makes good use of what might otherwise become waste, and the finished product is one of the best and simplest materials for improving your soil.
Through our trials over the years, we’ve found that using a compost bin is the most effective way of managing the composting process and that the type of bin you use can make a big difference.
With that in mind, we decided to look at what’s currently on the market and see which compost bins are the easiest to use and work most efficiently.
Alternatively you can buy ready-made soil improver