Leaf-heavy allotment heaps
You have a moist, aired bay that is mostly leaves, woody prunings and cardboard. A labelled compost maker, or more grass, fits that gap. Topline Garotta is the top pick for that heap. Bran does not belong on it.
The best compost accelerators, compared.
Top pick: Moutta bokashi 3 kg Best value: Bio-Composter 500 g – Highest price-within-job score, about £7.98 against a 5 m³ title claim, ahead of the tied Neudorff total. Updated October 2026.
A compost accelerator on amazon.co.uk is not one product. The shelf mixes nitrogen-style heap makers, liquids with no printed dose, microbial starters, bokashi bran for a sealed bucket, and mineral grit whose reviews describe stones. The Royal Horticultural Society says a heap with enough greens, browns, moisture and air usually needs no bought accelerator. Buy a heap maker only when nitrogen is the gap and the heap is already moist and aired. Buy bran only to ferment scraps, then bury them or add them to a heap. Scores follow stars, review volume, listing match, price within the job, and UK review usefulness. The [compost accelerator buying guide](/hub/raised-beds-greenhouses-and-compost/compost-accelerator/sub/compost-accelerator-buying-guide) names the job before the stars. A compost accelerator is a bought addition for a heap, a bin, or a sealed kitchen ferment. Heap powders, such as makers and granules, go on layers of garden waste and raw peelings.
A compost accelerator on amazon.co.uk is not one product.
Swipe for more
1-2 of 9Personal buying guide
Question 1 of 2
What are you feeding?
Moutta's 3 kg bag is £29.99, the highest cash price in this set, and the listing places the brand in France. You are told to add a thin layer of about 1–2 tablespoons at the end of each day, squeeze air out of the bag, and store it at room temperature. The amazon.co.uk line is 4.6 from 221 reviews, the highest star average here. In this capture only one review is marked United Kingdom, and that review is positive, so the other comments in the sample are not British shopper opinion. Those non-UK notes mention torn sachets, the cost of using bran often, smell, and a buyer who saw no change after moving from 1 kg to 3 kg. It fits a household that will dose a bokashi bin most days and wants the spoon measure printed before buying. It is a heavy outlay if you are only testing one bucket.
Pros
Cons
Best for: A household that adds food scraps most days and wants 1–2 tablespoons printed on the listing.
Less suitable: A one-off experiment, a brown garden heap, or a buyer who needs several United Kingdom reviews rather than the 221-review aggregate.
Specifications
Common questions
How much does the listing say to add?
A thin layer of about 1–2 tablespoons on the waste at the end of each day. Store at room temperature and squeeze air out of the bag.
Are the 221 reviews all from the UK?
The 4.6 from 221 is the amazon.co.uk aggregate. In this capture, one review is marked United Kingdom and is positive. The rest of the sample is mostly not UK-located.
What non-UK complaints appear in the sample?
Torn sachets, the cost of using bran often, smell, and one buyer who saw no change after 1 kg and then 3 kg.
Two 3.5 kg boxes give you 7 kg of Garotta compost maker for £17.99, about £2.57 a kilogram, and 151 amazon.co.uk reviews average 4.5. Buyers often say the heap warms or breaks down faster once the powder is on garden waste. This listing does not print a gram dose, so the rate has to come from the box that arrives. Split or leaking boxes in transit come up often enough to treat the packaging as a real fault. Rank 2 in Compost Accelerators is a sales position on that shelf, not a laboratory result. It is the top pick here for a brown, moist outdoor heap, and a clumsy buy if you only wanted one small box or a sealed kitchen ferment.
Pros
Cons
Best for: A moist, aired outdoor heap or dalek that is mostly leaves, woody prunings, and cardboard, where you will read the dose on the box.
Less suitable: A single small box, a sealed bokashi bucket, or a wormery.
Specifications
Common questions
How much Garotta does this bundle contain?
The listing is a pack of 2 x 3.5 kg. The parcel weight on the listing is 7.3 kg.
Does this listing print a dose?
No dose is printed in this amazon.co.uk capture. The bullets describe a biological accelerator and a warmer heap.
What do the UK reviews repeat?
151 reviews average 4.5. Buyers praise a faster or warmer heap. Several describe split or leaking boxes in transit.
Biorfe is 1 kg of wheat bran at £12.95, packed in Turkey, for an indoor or kitchen composter rather than a leaf heap. The listing says the bran makes waste ferment instead of rot, and the instruction is to sprinkle, with no grams given. It claims storage for up to 2 years at room temperature. The amazon.co.uk aggregate is 4.5 from 63 reviews. Only two captured reviews are marked United Kingdom: one reports food fermented in two weeks, with a pickled smell and a dry bag, and the other had not started. A further captured review says the pack arrived with no instructions, so treat this as a small bran refill for a sealed bin, not as a powder for dry leaves.
Pros
Cons
Best for: A flat or kitchen with a sealed bokashi bin and a need for about 1 kg of wheat bran.
Less suitable: A leaf heap, a dalek top-up, or anyone who wants a gram dose and a larger set of UK reviews.
Specifications
Common questions
Is this a compost maker for a leaf heap?
The listing says the bran makes waste ferment instead of rot, and the title points at an indoor or kitchen composter.
What did UK reviewers write?
Two captured reviews are marked United Kingdom. One says food fermented in two weeks with a pickled smell and a dry bag. The other had not started.
Does the listing give a gram dose?
No. It says sprinkle the bran on waste. One captured review says the pack arrived with no instructions.
The 3 litre Lava-Lite bag weighs 2.39 kg and is listed at £14.13. The title says natural beneficial bacteria for compost bins, while UK reviews in this capture describe pale stones and dust, and one reviewer says it is not an accelerator. The same review text is attached to the 1 litre listing, and both show 4.5 from 18, so the stars are one sample on two packs. A review in the file preferred the 3 litre size to the 1 litre on price, and another wanted a scoop. Rank 45 in Compost Accelerators does not identify the contents. Buy it only if you want mineral grit in a bin, and do not buy it as a proven inoculant.
Pros
Cons
Best for: Someone who has opened the bag, found mineral grit, and wants that grit in a compost bin.
Less suitable: Anyone buying beneficial bacteria, or anyone treating 4.5 from 18 as a separate sample from the 1 litre listing.
Specifications
Common questions
Is this a bacterial accelerator?
The title says natural beneficial bacteria. UK reviews in the capture describe pale stones and dust, and one says it is not an accelerator.
How big is the bag?
3 litres, item weight 2.39 kg, shelf price £14.13. A review in the file called the 3 litre size better value than 1 litre.
Are these the same reviews as the 1 litre listing?
In this batch the captured review text matches the 1 litre raw file, and both show 4.5 from 18.
This listing is a 1 litre Lava-Lite bag at 750 g and £9.76. The title presents an activator with beneficial bacteria, and the captured reviews, which match the 3 litre file, describe pale grey rocks and dust more like perlite than a culture. The unit-count field says 3,000 ml, which clashes with the 1 litre title and the 750 g weight. Stars are 4.5 from 18, the same line as the larger bag, not a second group of buyers. One review mentioned about £5.99 for a 1 litre bag when it was written, below this capture's £9.76. Buy it only if you already wanted a small bag of grit and can live with the conflicting size fields.
Pros
Cons
Best for: A small trial of mineral grit, if you already know the reviews describe stones and you can ignore the 3,000 ml unit-count line.
Less suitable: A bacterial accelerator, or a shopper who needs the title, the weight, and the unit count to agree.
Specifications
Common questions
Is the pack 1 litre or 3 litres?
The title and capacity line say 1 litre and the item weight is 750 g. The unit-count field says 3,000 ml.
What is in the bag, according to reviews?
The same UK review text as the 3 litre file: pale grey rocks and dust, compared with perlite, not a biological inoculant.
What is the shelf price in this capture?
£9.76. A review in the file mentioned about £5.99 for a 1 litre bag at the time of that review.
Neudorff Radivit is a 1 kg tub of granules at £12.53, and the amazon.co.uk aggregate is 4.4 from 166 reviews. The spec field states 15–20 g on each layer of kitchen and soft garden waste. A label-style block pasted inside a captured review puts coverage at about 2 m³ or 30 m² per kilogram and says not to use Radivit with compost worms. None of the 33 captured reviews is marked United Kingdom, so the star average is not a sample of British gardeners in this file. Extra rates for lawn, leaves, and shredded prunings sit only inside that pasted block. It belongs on a garden heap if you can follow the 15–20 g line, and it does not belong in a wormery.
Pros
Cons
Best for: A garden compost heap of kitchen peelings and soft waste, dosed at 15–20 g a layer, with no worm bin involved.
Less suitable: A wormery, or a buyer who wants UK-located reviews in this capture.
Specifications
Common questions
Can it go in a wormery?
A label-style block inside a captured review says not to use Radivit with compost worms. There is no separate spec row for that warning.
What dose is on the listing?
The spec field is a Dutch line for 15–20 g per layer of kitchen and soft garden waste. Fuller layer rates appear only inside that pasted review.
Are there UK reviews in the capture?
The aggregate is 4.4 from 166 on amazon.co.uk. None of the 33 captured reviews is marked United Kingdom.
The 500 g Bio-Composter pack is £7.98, and the title says that weight covers 5 m³ of mixed waste. amazon.co.uk shows 4.1 from 103 reviews, with rank 21 in Compost Accelerators. No gram-per-layer dose is printed, and the material field says Wood, which does not tell you how to sprinkle a bacterial starter. One UK review says the instructions on the pack were impossible to read and that nothing had happened yet. A separate review says a large pile broke down and that many leatherjackets later turned up in two vegetable beds; that is one account, not an ingredient on the label. On shelf price against the title's coverage figure, it is the best value in this comparison, provided the pack you open states a dose. If it does not, £7.98 is only a cheap unknown.
Pros
Cons
Best for: A large mixed heap where £7.98 against the title's 5 m³ figure is the budget, and the pack you receive shows a readable dose.
Less suitable: Buyers who need grams on the amazon.co.uk page before they pay.
Specifications
Common questions
How much waste does the title say it treats?
The title says 5 m³. The pack weight is 500 g. No dose in grams per layer is in the listing.
What do reviews say about the instructions?
One UK review says the instructions on the pack were impossible to read, and that nothing had happened yet.
What is the leatherjacket comment?
One UK reviewer says a large pile broke down and that they later found many leatherjackets in two vegetable beds. That is one review, not a labelled ingredient.
This clear 500 ml bottle is £6.21, with the United Kingdom given as the country of origin, and 190 reviews average 4.0. The listing says it speeds heaps and bins from autumn to spring, and it does not print a dose. Reviewers say the bottle never tells you whether to use the liquid neat or diluted, or whether the whole 500 ml is one application. One review calls the result okay but not as good as Garotta, while others say a bin has started or that nothing happened. Rank 7 in Compost Accelerators only records sales on that shelf. A low shelf price does not replace a missing instruction, so leave it until a dose is printed.
Pros
Cons
Best for: Only a buyer who can read a neat-or-diluted dose on the bottle that arrives.
Less suitable: Anyone who needs a printed rate before paying, or who is comparing results with Garotta.
Specifications
Common questions
Is a dose printed?
Not in this listing. UK reviews say the bottle does not say whether to use it neat or diluted, or whether the whole bottle is one dose.
Where is it made, according to the listing?
Country of origin is United Kingdom. The bottle size is 500 ml and the item weight is 550 g.
How does it compare with Garotta in the reviews?
One review says it is okay but not as good as Garotta. Others say a bin has started, or that nothing happened.
The title offers a Levington 3.5 kg compost maker at £14.79 in granule form. The brand field reads Fixtures Business & Homewares, the manufacturer line reads Fixtures, and the part number is LevLime7kg, which does not match a 3.5 kg compost-maker name. The unit count is 3,500 g and the origin is given as the United Kingdom. This file has no customer-review line and no review text, so there is no star average to weigh. Dose, system, and food-scrap suitability are all missing. Until the brand, the part number, and at least one review describe the same product, you cannot treat the title as the contents of the parcel.
Pros
Cons
Best for: Hold the purchase until the brand field, the part number, and a review sample agree with the Levington title.
Less suitable: Anyone choosing a compost maker from the title alone.
Specifications
Common questions
Who is the brand on this listing?
The title says Levington. The brand field says Fixtures Business & Homewares and the manufacturer says Fixtures.
What is the part number?
LevLime7kg, which does not match a 3.5 kg compost-maker title. The unit count is 3,500 g.
Is there a star rating?
This raw file has no customer-review line and no review text.
Nine compost accelerators are on this page. Scores use the amazon.co.uk capture from 15 October 2026. There is no laboratory test. Stars contribute up to 30 points, review volume up to 20, listing match up to 25, price within the job up to 15, and UK review usefulness up to 10. Bran is not scored against heap powder. Lava-Lite's shared 18-review text is counted once per ASIN, not as two samples. Non-UK review text on Moutta, Biorfe and Neudorff is not scored as British opinion.
Stars
30%The amazon.co.uk star rating, converted as a share of 30. A listing with no review line scores 0 on this block.
Review volume
20%A log scale of the amazon.co.uk review count, capped at 20. A count of 0 scores 0. Shared Lava-Lite text is one sample, not two.
Listing match
25%Title, form and reviews should describe one job. A printed dose adds points. A brand clash or a title that disagrees with the reviews deducts.
Price within the job
15%Shelf price against pack size for that job only. Bran is not scored as a cheap heap powder, and grit is not scored as an inoculant.
UK review usefulness
10%Whether the captured reviews are marked United Kingdom and say something specific. Star aggregates stay the amazon.co.uk figures.
Name the job before you compare stars. Heap powder, a dose-less liquid, bokashi bran and mineral grit are different purchases. Prices on this page are amazon.co.uk captures from 15 October 2026, from about £6.21 to about £29.99.
A compost accelerator is a bought addition for a heap, a bin, or a sealed kitchen ferment. On amazon.co.uk that search is not one product. Heap powders, such as Garotta-type makers and Neudorff Radivit granules, go on layers of garden waste and raw peelings. BritishBasics is a 500 ml liquid at about £6.21 that claims to speed heaps and bins and prints no dose. Bio-Composter is 500 g at about £7.98, with a title that says 5 m³ and a material field that says Wood.

Bokashi bran ferments scraps in a sealed bin. Heap powder goes on garden waste. Swapping them does not speed the other system.
Westland's current Garotta page and older Barrs and Crocus pages do not use the same rate. Neudorff prints 15–20 g per kitchen layer. Do not average those figures onto a bottle that prints nothing.
Lava-Lite titles say beneficial bacteria, and the UK reviews describe stones. Neudorff says do not use Radivit with compost worms. A wet, slimy bin needs air and a drier mix, not another dose.
Name the job before you compare stars. A brown, slow outdoor heap needs a nitrogen-style maker or more greens. A kitchen bucket for cooked food needs bokashi bran. A wormery must not get Neudorff Radivit. A cold dalek in January is usually a season problem, not a missing bottle. Heap powders in this set are Topline Garotta, two 3.5 kg boxes at about £17.99, and Neudorff Radivit, 1 kg at about £12.53.
Read the dose on the pack you hold. Westland's current Garotta page says 200–250 g on each 30 cm layer and about 4.5 litres of water if the waste is dry. Older Barrs and Crocus pages still say 2–3 tablespoons per square metre on an 8 cm layer. Do not average them. The Topline listing itself does not print a gram dose. Neudorff's spec field states 15–20 g per kitchen layer. Moutta prints 1–2 tablespoons a day. Biorfe says sprinkle.
Three typical situations, each with a recommendation from this comparison.
You have a moist, aired bay that is mostly leaves, woody prunings and cardboard. A labelled compost maker, or more grass, fits that gap. Topline Garotta is the top pick for that heap. Bran does not belong on it.
You ferment kitchen scraps in a bokashi bucket, then bury them or add them to a heap. Moutta prints 1–2 tablespoons a day. A 7 kg Garotta box is the wrong pack for one kitchen bucket.
You want the lowest useful shelf price against a stated coverage figure. Bio-Composter is about £7.98, and the title says 500 g covers 5 m³. Use it only if the pack you open shows a readable dose.
Nine listings do not share one job. Topline Garotta, two 3.5 kg boxes at about £17.99, is the top pick for a brown, moist outdoor heap: 4.5 from 151 amazon.co.uk reviews and the highest card score. The listing still omits a gram dose, and reviews mention split boxes. Bio-Composter, 500 g at about £7.98, is the best value because its price block leads the set, even though the total ties Neudorff Radivit. Bran, liquid and grit stay separate purchases.

Bio-Composter 500 g
Highest price-within-job score, about £7.98 against a 5 m³ title claim, ahead of the tied Neudorff total.
Editorial

Peter F. is the editor for DIY & tools at productscompared.co.uk. Comparisons in this category are checked against amazon.co.uk listings, review evidence and public UK sources.
Guides on what to look for, how to use a product, and common mistakes.
Public UK and manufacturer sources from the research digest, last checked on 15 October 2026.
This article contains affiliate links. If you buy through these links, we may earn a commission at no extra cost to you. The cards use amazon.co.uk listing data and public UK sources. They are not a laboratory test.