Lawn & garden
Westland Epsom Salts dupe
Why pay around £6.50 for Westland? The bulk active is Magnesium sulphate heptahydrate (Epsom salts) — 59% less per working litre than a typical shelf pack.
From the retail pack to the active and the mix
1 · Retail
Westland Epsom Salts
1.5 kg box · £6.50 typical snapshot
None (crystals)
2 · Active
Magnesium sulphate heptahydrate
100% on the label
10034-99-8MgSO4·7H2O
Bulk Magnesium sulphate heptahydrate (Epsom salts)
3 · Mix
10 g/L as a foliar drench; 20 g/m² on soil
£0.02 per working litre · 59% less than the shelf pack
- Active
- Magnesium sulphate heptahydrate
- CAS
- 10034-99-8
- Dupe
- Magnesium sulphate heptahydrate (Epsom salts)
- Saving
- 59% / L
Saving is per litre of working-strength mix versus a typical pack price, not versus the DIY kit total. Shop prices move — always check the listing.
Label teardown
What the pack promises versus what the label chemistry actually is.
The marketing claim
“Greener leaves and better flowers”
The chemical reality
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).
Active vs filler
100% Magnesium sulphate heptahydrate · 0% carrier / filler — None (crystals)
- Typical retail
- £6.50
- 1.5 kg box
- Estimated active cost
- £2.70
- Scaled from bulk £8.99 / 5 kg
- Indicative markup
- 2.4×
- Snapshot maths, not a live shop price
The Marketing Claim & The Catch
A 1.5 kg box pack of Westland Epsom Salts typically retails around £6.50 in lawn & garden. That is a UK shelf-price snapshot for the maths on this page — not a live shop quote or a manufacturer RRP. Listings, sizes and deals move. The marketing line is that you are buying a finished lifestyle product, not a weighed chemical.
On the pack: Greener leaves and better flowers; and Corrects magnesium deficiency in tomatoes and citrus.
The catch: 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).
- “Greener leaves and better flowers”
- “Corrects magnesium deficiency in tomatoes and citrus”
Proprietary Blend & Dosage Breakdown
The labelled active is Magnesium sulphate heptahydrate at 100%. Everything else in the pack is none (crystals).
Even when the pack is sold as “pure” or ready-to-use, the dose that actually does the work is Magnesium sulphate heptahydrate. The rest is how they get it into a bottle you will pick up.
Branded working strength is whatever comes out of the bottle. The bulk alternative is 100% Magnesium sulphate heptahydrate (Epsom salts), mixed to 10 g/L as a foliar drench; 20 g/m² on soil.
- Labelled active
- Magnesium sulphate heptahydrate
- 100%
- Carrier
- None (crystals)
- Retail pack
- 1.5 kg box · £6.50
The Active Chemical Alternative (Dupe Stack)
The dupe stack is Magnesium sulphate heptahydrate (Epsom salts) at 100% bulk. Indexed as CAS 10034-99-8, formula MgSO4·7H2O. Buy it as 5 kg for around £8.99 from Amazon UK.
Working strength: 10 g/L as a foliar drench; 20 g/m² on soil. Indicative cost £0.02 per diluted litre — 59% below a typical branded pack on a per-litre basis, before you reuse leftover bulk.
Follow the mixing method and the supplier SDS. Wear the listed PPE. Do not mix incompatible oxidisers, acids or ammonia.
- Food/technical grade crystals. Dissolve 10 g in 1 litre for a foliar feed, or broadcast 20 g/m² around hungry tomatoes and water in.
- 5 kg is more than three Westland boxes. Store dry — it cakes.
- This corrects magnesium. It is not a complete fertiliser and it is not a medicine.
Dilution recipe
5 L sprayer
Working strength 10 g/L as a foliar drench; 20 g/m² on soil. Educational estimate from the listed ratio — check the SDS before you mix.
Chemical
50 grams
Magnesium sulphate heptahydrate (Epsom salts)
Water
5 litres
Carrier / diluent
0% concentrate · 100% water by working volume (solids are dissolved into the water share).
Required PPE
Loading calculator…
Side-by-Side Price & Potency Comparison
Head-to-head comparison
| Measure | Retail brandedWestland | Raw active dupeDupeStack |
|---|---|---|
| Product | Epsom SaltsAmazon UK search — listing, not a confirmed seller | Magnesium sulphate heptahydrate (Epsom salts) |
| Pack / unit | 1.5 kg box · £6.50 | 5 kg · £8.99 |
| Active | Magnesium sulphate heptahydrate at 100%Carrier: None (crystals) | 100% bulkMgSO4·7H2O |
| CAS number | Not disclosed on pack | 10034-99-8 |
| Working strength | Ready-to-use pack | Dilute 10 g/L as a foliar drench; 20 g/m² on soil |
| Cost per litre | £6.50 / pack | £0.02 / L mixed from bulk |
| Headline saving | Baseline | 59% cheaper |
| COSHH / PPE | Follow the branded SDS | Gloves. Chemical-resistant gloves (nitrile or neoprene) |
Active ingredient and cheaper alternative — FAQ
What is the active ingredient in Westland?
Westland Epsom Salts is labelled as Magnesium sulphate heptahydrate at 100%. The carrier is None (crystals). Pack size: 1.5 kg box. The bulk equivalent we index is Magnesium sulphate heptahydrate (Epsom salts) (CAS 10034-99-8).
Is Magnesium sulphate heptahydrate (Epsom salts) safe on lawns?
Used at the listed working strength (10 g/L as a foliar drench; 20 g/m² on soil), the dupe is the same chemistry as the branded pack for lawns, beds and pots. That is not a blanket all-clear: read the supplier SDS, wear the listed PPE, keep acids away from hypochlorite, and follow UK HSE/COSHH rules. Wellness teardowns are supplements, not medicines.
Is there a cheaper alternative to Westland Epsom Salts?
Yes. The bulk equivalent is Magnesium sulphate heptahydrate (Epsom salts) (CAS 10034-99-8). Indicative saving 59% per working litre versus a pack that typically retails around £6.50. Working strength: 10 g/L as a foliar drench; 20 g/m² on soil. Live shop prices move.
How do you mix the Epsom Salts dupe stack?
Food/technical grade crystals. Dissolve 10 g in 1 litre for a foliar feed, or broadcast 20 g/m² around hungry tomatoes and water in. 5 kg is more than three Westland boxes. Store dry — it cakes. This corrects magnesium. It is not a complete fertiliser and it is not a medicine.
DupeStack provides chemical concentration data and educational mixing guides only. Wellness pages compare food supplements, not medicines or prescribed treatments. Always review the supplier Safety Data Sheet (SDS) and comply with UK Health and Safety Executive (HSE) and COSHH regulations when handling concentrated substances. Mixing and storage are at your own risk. Some links are affiliate advertisements (Amazon Associates, eBay Partner Network, and Awin when those programmes are live). Commissions do not change listed concentrations or calculator output.
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£16.50Save 59% / L
Indicative DIY stack