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Category hub
Feeds, moss killers and kelp extracts broken down into agricultural-grade salts and powders.
Teardowns
13
Typical saving
65%
Steepest gap
Evergreen Complete 4-in-1 Lawn Feed & Moss Killer
Lawn feeds, moss killers and houseplant drops are agricultural salts and kelp, portioned into small boxes. The analysis on the pack (NPK, iron, potash) is the only number that matters.
Weigh granules per square metre. Do not pile fertiliser against stems, and keep soluble iron off pale stone if you want to avoid rust stains.
Organic-looking branding does not change the salt. Sulphate of potash and ferrous sulphate still need gloves and a dry store.
This hub currently covers 13 lawn & garden teardowns. Typical saving versus a branded pack is about 65% per working litre. The steepest gap today is Evergreen Complete 4-in-1 Lawn Feed & Moss Killer at 91%. Snapshot retail prices start around £4.99 — live shop listings move.
Lawn & garden
Miracle-Gro
A watered-down cold-pressed kelp extract. Soluble Ascophyllum nodosum powder is the same crop, sold by the kilogram to hydroponic growers, at a fraction of the bottled price.
Lawn & garden
Evergreen
The moss-blackening punch is ferrous sulphate — the same agricultural iron used on bowling greens. The 4-in-1 box is mostly filler, NPK dust and a brand. Buy the salt.
Lawn & garden
Growmore
7-7-7 is a commodity NPK blend. The cardboard box is a portioned sack of agricultural compound fertiliser. Buy it by the 25 kg bag from a merchant, not 4 kg at a time from a garden centre.
Lawn & garden
Miracle-Gro
A dilute bottle of soluble NPK. Hydroponic 20-20-20 (or similar) powder is the same three numbers, un-dyed and un-marketed, at a gram per litre instead of a capful of coloured water.
Lawn & garden
Mo Bacter
The moss dies because of high potash, not a magic organic patent. Sulphate of potash (0-0-50) supplies the same K2O without iron staining; a cheap Bacillus or compost-tea inoculant does the digestion step. A 20 kg 5-5-20 bag is mostly filler next to 10 kg of 50% K2O.
Lawn & garden
Doff
A 75 g tub is 74.9 g of talc carrying 75 mg of IBA. That is about £67/kg for cosmetic powder. 0.5 g of pure IBA in 500 g of unscented talc is the same 0.1% dip.
Lawn & garden
SB
Dilute foliar urea plus a potassium fatty-acid soap that smothers soft-bodied insects. A 500 ml bottle at 10 ml/L makes about 50 litres; the same working spray from bulk soap and urea is pence per litre.
Lawn & garden
Levington
A dilute high-potash bottle with a pinch of kelp. Soluble tomato feed around 4-4-8 (or 6-5-12) at 2 g/L is the same three numbers without the green dye. This is not Miracle-Gro 20-20-20 — tomatoes want potassium.
Lawn & garden
Westland
The garden-centre box is agricultural Epsom salts with a picture of a tomato. MgSO4·7H2O is a commodity desiccant and bath salt. Buy it by the 5 kg bag, not 1.5 kg at a time. This is not BetterYou magnesium oil (that is chloride).
Lawn & garden
Westland
21% nitrogen as ammonium sulphate. The cardboard box is a portioned sack of a fertiliser merchants sell in 25 kg lots. It greens grass. It also acidifies — do not pile it on chalk-hating stone paths.
Lawn & garden
Doff
Metaldehyde is gone. What remains is ~1% ferric phosphate in a cereal pellet. The 800 g tub is a small bag of the same bait sold in 2–5 kg buckets to allotmenteers. You are paying for the child-resistant lid.
Lawn & garden
Vitax
This is not ferrous sulphate (that is Evergreen moss killer) and it will not blacken a pale patio the same way. EDDHA/EDTA iron stays available on chalky soil. Four 20 g sachets are a tiny bag of the 6% chelate sold in 250 g tubs to nurseries.
Lawn & garden
Westland
This is not Tomorite (a dilute 4-3-8 bottle) and it is not 20-20-20. Potassium nitrate is 13-0-46: nitrogen plus potash in one salt. The garden-centre 1.5 kg box is agricultural KNO3 with a tomato on the front. Buy it in 5 kg.