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How to read a fertiliser label

Updated: October 2026

You have an amazon.co.uk tab open and the technical table does not show the three nutrient figures you expected. Learning how to read a fertiliser label, on this shelf, means separating that table from the statutory pack marking. This page uses the eleven liquids in our [cannabis fertiliser comparison](/hub/fertiliser-soil-and-bark-mulch/cannabis-fertiliser). The Products Compared editorial team read those listings on 19 October 2026 and did not weigh a bottle or test a nutrient. A qualifying purchase can earn a commission at no extra cost to you. Nothing below is a mixing plan.

You have an amazon.co.uk tab open and the technical table does not show the three nutrient figures you expected.

Our top picks

CANNA CANNA Coco A and B 1L set

Best overall

CANNA CANNA Coco A and B 1L set
9.4/10about £17.56
View offer
Advanced Nutrients Advanced Nutrients Big Bud 250 ml

Alternative

Advanced Nutrients Advanced Nutrients Big Bud 250 ml
9.0/10about £12.25
View offer
Advanced Nutrients Advanced Nutrients Bloom pH Perfect 500 ml

Preis-Tipp

Advanced Nutrients Advanced Nutrients Bloom pH Perfect 500 ml
9.0/10about £10.62
View offer
On this page
  1. 1.What a UK fertiliser label is meant to show
  2. 2.What these listings actually print
  3. 3.Two bottles, and two volume figures
  4. 4.Language and brand phrases

What a UK fertiliser label is meant to show

The Fertilisers Regulations 1991, Schedule 2, ask for markings that are clear, in English, conspicuous and indelible, and they use the symbols N, P2O5 and K2O in that order. Phosphorus and potassium are often shown as oxides, with the element in brackets. A lawful pack marking and an Amazon bullet list are not the same object. If the symbols are missing from the listing, the honest cell is blank. Inventing 0-4-4 because another brand's page uses a similar name would break that rule.

What these listings actually print

None of the eleven technical tables print N, P2O5 and K2O. The comparison therefore leaves NPK blank on every row. Watch the fields that look numerical and are not an analysis. Bio Flores and Bud Ignitor carry a mixing-ratio field of 1:0:0. The second Coco A+B listing carries 4:4:1. Those strings stay raw fields. They are not adopted as NPK panels, and they are not a recipe. Advanced Nutrients' own Big Bud Coco page prints an NPK of 0-4-4. That figure is not in the amazon.co.uk technical table for B00V4QS74K or B07D3ZGPY6, so it stays off the comparison. If you cite it, cite the maker, not Amazon. The buying guide decides which job to buy.
CANNA CANNA Coco A and B 1L set

Testsieger

CANNA CANNA Coco A and B 1L set
9.4/10about £17.56
View offer

Two bottles, and two volume figures

A and B means two concentrates sold as a set. CANNA's own note on Coco A and B says the parts are kept apart because concentrated calcium and phosphate can form a residue if they are poured together. That is a reason the pack is two bottles. Both B003VN7272 and B0090HMR9G are A and B coco sets. Every other ASIN here is a single bottle. Three listings then disagree with themselves about size. About 8.45 fl oz is in the region of 250 ml, and 8.45 millilitres is not, so the unit word is the conflict, not a third size you should average. The coco or soil page is where the medium word is settled.

Language and brand phrases

Schedule 2 expects the marking to be in English. On B003VN7272, one reviewer says the instructions on the B bottle are in French. On B0090HMR9G, a UK review says there is not a word of English on the bottle and that the text is French. A French-only bottle is a problem for a UK shopper who needs the statutory line. It does not by itself prove the contents differ from the English-labelled set. pH Perfect is the product name on the 500 ml Bloom bottle, B00V4QR3MC. Reviewers of Big Bud Coco say that bottle is not pH Perfect and that it moved the pH. The role split is on bloom booster or base fertiliser.

Common questions

What do the three NPK numbers mean in UK labelling?
In the Fertilisers Regulations 1991 the usual order is N, then P2O5, then K2O. N is nitrogen. P2O5 and K2O are the oxide forms of phosphorus and potassium, and labels often add the element in brackets. The RHS describes that pattern for garden fertiliser packets. None of the eleven Amazon tables in this comparison actually print those three symbols.
Why is NPK missing on these Amazon tables?
The technical table in each saved listing has no nitrogen, phosphorus or potassium figure. The comparison records that absence rather than borrowing a number from a manufacturer page or from another pack size. A mixing-ratio field is not a substitute. The statutory marking, if it is on the bottle, was not copied into these listings.
What does A and B mean?
A and B is a two-bottle set. In this folder that is CANNA Coco A and B, ASINs B003VN7272 and B0090HMR9G. CANNA says the concentrates are kept apart because calcium and phosphate can form a residue if they are poured together neat. The other nine listings are single bottles. A and B does not mean two ratings or two pack sizes.
Why might a UK buyer see a French-only bottle?
A review on B0090HMR9G says the bottle has no English and that the text is French. A review on B003VN7272 says the B bottle's instructions are in French. UK marking rules expect English. The review is not a full audit of every unit, and it is enough reason to check the label when the parcel arrives.
Which ASINs print two different volumes?
B004TENZMI prints 250 ml, the text 250 litres, and a 240 ml liquid-volume field. B00V4QS74K prints 250 ml against a unit count of 8.45 millilitres and a liquid volume of 8.45 fl oz. B0090HMR9G prints 1L against a liquid volume of 2 litres and a weight of 2.48 kg. Do not average those figures into a new size.
Does pH Perfect on one title apply to the brand?
No. It is the name of Advanced Nutrients Bloom, B00V4QR3MC, the 500 ml bottle at £10.62. Reviewers of Big Bud Coco say that product is not pH Perfect. The phrase is not a property of Bud Candy, Bud Ignitor or the non-coco Big Bud listing either.
Is a mixing-ratio field of 1:0:0 an NPK?
No. Bio Flores and Bud Ignitor print 1:0:0 in a mixing-ratio field, and another coco listing prints 4:4:1. Those are raw table strings. They are not a verified N, P2O5 and K2O panel, and they are not instructions to follow from this page.

Related pages

Cannabis fertiliser comparison

Cannabis fertiliser buying guide

Coco fertiliser or soil fertiliser

Bloom booster or base fertiliser

Best cannabis fertiliser: pick one job, skip the rest

Sources

Public UK and trade sources from the research digest, used for this page in October 2026. Prices, stars and review counts are from the eleven amazon.co.uk listings captured on 19 October 2026. There is no laboratory test and no harvest measurement. A Bio name is not an organic certificate. Buying a bottle does not make cannabis cultivation lawful.

  1. Misuse of Drugs Act 1971, section 6 (retrieved 19 October 2026)
  2. Misuse of Drugs Act 1971, Schedule 4 (retrieved 19 October 2026)
  3. Misuse of Drugs Regulations 2001, regulation 12 (retrieved 19 October 2026)
  4. GOV.UK, hemp licensing (retrieved 19 October 2026)
  5. GOV.UK, manufacturing and marketing fertilisers (retrieved 19 October 2026)
  6. Regulation (EC) No 2003/2003, Article 9 (retrieved 19 October 2026)
  7. Fertilisers Regulations 1991, Schedule 2 paragraph 6 (retrieved 19 October 2026)
  8. ASA CAP Code 3.7 (retrieved 19 October 2026)
  9. Greens Horticulture, nutrients for soil, coco and hydro (retrieved 19 October 2026)
  10. GroWell, how to choose nutrients (retrieved 19 October 2026)