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Blackwalls Compost Converter

Blackwall Compost Converter review

A competitively priced composter, with good eco-credentials.

Our rating 
4.0 out of 5 star rating 4.0

In a nutshell

A BBC Gardener’s World Best Buy winner, the Blackwalls Compost Converter was voted the best budget model, being exceptionally keenly price for size. Scores high on eco-credentials as made totally or mostly from recycled plastic. Comes with an impressive seven-year warranty too.
Design and setup
5.0 out of 5 rating 5.0
Ease of use
3.0 out of 5 rating 3.0
Compost quality
3.0 out of 5 rating 3.0
Value for money
5.0 out of 5 rating 5.0
Pros: Low price and long warranty

Totally or mostly recycled plastic

Optional base plate for siting on hard surfaces
Cons: Thin, non-ventilated construction

Slow to compost

Only one access hatch
Skip to view product specifications

Buy the Blackwall Compost Converter (green model) on Amazon

Buy the Blackwall Compost Converter on Evergreener

What is the Blackwalls Compost Converter like and where can I place it?

The bin consists of a one-piece cone shaped body with a snug-fitting removable lid and single hatch, which is easy to open and refit. The bin needs to be sited directly on soil to ensure drainage and good microbial action, and in a part or fully shaded spot. A base plate can be added if the bin has to be sited on a hard surface (price £14.99). It’s available in black or green. A smaller 220 litre capacity model is also available, but with very little difference in the size, you’re better off with the larger one unless space is at an absolute premium.

What is the Blackwalls Compost Converter like to set up and use?

There’s no assembly apart from popping on the lid and hatch – just put the bin on the ground and start filling. The sides are single-skin plastic with no additional ventilation or insulation, so it was the slowest to produce compost in our trial. All waste shrinks and settles down as it composts, although with this bin the waste shrunk away from the sides but didn’t spread out as it settled, so it needed a bit of stirring every so often so the bin filled to capacity. Finished compost can be harvested from the hatch at the base, though if the whole bin is full of finished compost, it’s easier simply to lift off the bin – it’s sufficiently lightweight.

What can I put in the Blackwalls Compost Converter?

Garden waste including lawn mowings, chopped up prunings and weeds, brown cardboard and plain paper, kitchen waste such as vegetable peelings, tea bags and coffee grounds, but not cooked food. Note the optional base plate is to improve drainage but doesn’t make the bin vermin-proof to take cooked food.

Who is the Blackwalls Compost Converter most useful for?

A basic and budget compost bin that would be adequate for anyone with a small garden. In a tiny space where little waste is produced and there’s room for just one bin, the compost can be harvested from the base while waste is added in the top. However, as composting takes at least six months, it’s likely you’ll need more than one bin.

Is the Blackwalls Compost Converter value for money and is it built to last?

The simple design means there’s very little to go wrong or break: even the thinner slots on the hatch appear sturdy and durable. This bin is good from an eco-friendly point of view, especially the black model which is made totally from recycled plastic (the green model is 70 per cent recycled). There’s an impressive seven-year warranty, too.

Buy the Blackwall Compost Converter (black model) on Amazon

Buy the Blackwall Compost Converter (green model) on Amazon


Buy the Blackwall Compost Converter on Evergreener

Product Specifications


Brand Blackwall
Name Blackwall Compost Converter
Model Blackwall 330-Litre Compost Converter
Price £28.00


Material Recycled plastic
Height 100cm
Width 80cm
Depth 80cm
Capacity 330l
Warranty 7YEAR
Lifetime Warranty No
Feature notes

A smaller, 220-litre model is also available


The black model is made from 100 per cent-recycled plastic, the green model from 70 per cent-recycled plastic