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Effective microorganisms buying guide

Updated: 23 October 2026

A Saturday search for soil microbes on amazon.co.uk often ends with three liquids and a powder that share almost none of the work. EM-1 is a dormant mother culture you brew. Microferm is already fermented liquid you dilute. BioBizz Microbes is a 150 g powder for a different feed. This effective microorganisms buying guide is the fork: match the stage to the job you will do this month. The [effective microorganisms comparison](/hub/diy-supplies/effective-microorganisms) holds the six listings and the badges. Peter F. read those listings and public UK seller pages. We did not ferment a jar. A qualifying purchase through our links can earn a commission at no extra cost to you.

A Saturday search for soil microbes on amazon.co.uk often ends with three liquids and a powder that share almost none of the work. EM-1 is a dormant mother culture you brew.

Our top picks

Moutta Microferm 5 litre ready liquid

Best overall

Moutta Microferm 5 litre ready liquid
7.5/10about £44.90
View offer
Moutta EM-1 1 litre stock

Rank 2

Moutta EM-1 1 litre stock
7.8/10about £39
View offer
BioBizz BioBizz Microbes 150 g

Alternative

BioBizz BioBizz Microbes 150 g
7.2/10about £49
View offer
On this page
  1. 1.Three different products share the search
  2. 2.What you must already own
  3. 3.What the listing figures do not prove
  4. 4.If you will not brew

Three different products share the search

Moutta's EM-1, made by Agriton in Belgium, is the stock solution in this set. Moutta Farm's own page puts the split in one sentence: EM-1 stays dormant until you brew it, and Microferm is already active. Microferm is the ready liquid in the same brand family. The titles say ready-to-use. You dilute it. You do not start a second fermentation. If you will not keep a warm airtight jar this month, that is the bottle to open, and the condition sits on the EM-1 or Microferm page. BioBizz Microbes stays because the same search drops a powder into the basket. The listing ratio prints 0.2–0.4 mg per litre. The manufacturer's sheet is in grams, about 0.2–0.4 g per litre. It asks for no molasses, and it is not bokashi bran. None of these six ASINs is inoculated bran.

What you must already own

EM-1 is the cheaper liquid on the garden only after the brew succeeds. UK sellers describe unsulphured molasses, water that has lost its chlorine, and a jar you can seal and burp for about seven to ten days. Moutta's recipe is 5 percent EM-1, 5 percent molasses, and 90 percent water: 100 ml of stock, 100 ml of molasses, and 2 litres of water in their example. The 1 litre amazon file also prints a mixing ratio of 1:10. Brand pages do not use that figure for activation. Follow the notice in the box when it matches the 5 percent method. Smell, pH, and what to tip away are on the how to activate EM-1 page. Microferm skips that cupboard. The amazon files do not print a dilution rate.
Moutta Microferm 5 litre ready liquid

Testsieger

Moutta Microferm 5 litre ready liquid
7.5/10about £44.90
View offer

What the listing figures do not prove

Every EM-1 size prints 4.5 from 27 ratings, with the same short reviews, and those reviews are not United Kingdom write-ups of that canister. Each Microferm file has one rating. Neither is a dose or a fish-safety test, even where the browse node says Moss Control. No file prints a MAPP number. The Health and Safety Executive treats a soil-life claim as different from a pesticide claim. A sentence about fighting fungus or suppressing disease needs authorisation before it is advertised. A four-year field abstract by Mayer and colleagues found that an EM spray on its own did not differ from the untreated control, and that effects seen with bokashi also appeared when the EM had been sterilised.

If you will not brew

If you will not brew, Microferm is the stage that matches the month. The 10 litre canister is the large outlay, about £30 per litre of concentrate, and it is still dormant stock. A specialist ticket is a different shelf: Dr Forest lists a litre of concentrate at £25, and Wiltone has listed a litre near £21.59 including VAT. Those figures are not the amazon captures.

Common questions

Is EM-1 ready to spray?
The canister is dormant stock. Moutta's bullets require molasses and anaerobic conditions, and UK sellers describe a sealed brew of about a week to ten days before you have a short-life liquid to dilute. Microferm is the title that already says ready-to-use. You still dilute that one from the seller sheet.
When is Microferm the simpler buy?
Choose it when you will not keep a warm jar this weekend. The 2 litre pack is the smaller outlay at £27.99. The 5 litre pack is the lower price per litre, about £8.98. Both files have a single rating, so the simpler path is a stage choice, and the stars do not carry it.
Does the 250 ml canister need molasses too?
Yes. It is the same mother culture as the 1 litre and the 10 litre files, at £21.99, which is about £88 per litre of concentrate. This file does not print a mixing-ratio field. Unsulphured molasses and dechlorinated water are still the kit if you want activated liquid from it.
Is the 150 g powder the same culture?
BioBizz Microbes is a separate powder at £49. The brand sheet names Trichoderma and Bacillus and a weekly gram dose. The amazon line prints milligrams per litre, and the unit-count line and the 150 g weight line do not agree as printed. Read the gram sheet. There is no molasses step on this listing.
Can I use these bottles as a pesticide or a moss killer?
None of the six ASINs prints a MAPP number. A nutrition or soil-life claim sits apart from a pest or disease claim. The Microferm browse node says Moss Control. That heading is catalogue placement, not a trial result in the file.
Are the 27 stars a UK test of each size?
The 4.5 from 27 is the same line on the 250 ml, the 1 litre, and the 10 litre files. None of those reviews is marked United Kingdom, and none describes the 10 litre pack. Treat it as one thin shared sample, then choose by stage.

Related pages

Effective microorganisms for bokashi

Effective microorganisms

Best effective microorganisms for soil and compost

EM-1 or Microferm: dormant culture or ready liquid

How to activate EM-1 mother culture in a sealed jar

Sources

Public UK sources and the amazon.co.uk listings compared on this page. Updated 22.10.2026.

  1. HSE: Biostimulants (retrieved 22.10.2026)
  2. HSE: Biopesticides (retrieved 22.10.2026)
  3. Regulation (EU) 2019/1009, Annex I (retrieved 22.10.2026)
  4. The Fertilising Products Regulations 2020 (retrieved 22.10.2026)
  5. RHS: Bokashi composting (retrieved 22.10.2026)
  6. Agriton UK: EM-1 (retrieved 22.10.2026)
  7. Moutta Farm UK: EM-1 mother solution (retrieved 22.10.2026)
  8. BioBizz: Microbes (retrieved 22.10.2026)