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Iron Sward Liquid – Liquid Iron for Lawns 6% Fe

Iron Sward Liquid – Liquid Iron for Lawns 6% Fe

Year-round · liquid concentrate

Liquid iron for a deeper, tougher green

£6.95
£6.95
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  • ✓Deep green colour without a growth spurt
  • ✓6% iron solution - works from the day you spray it
  • ✓Hardens turf and checks moss in autumn and winter
  • ✓1-2 ml per m² - a 100 ml bottle treats up to 100 m²
Size

A concentrate — dilute with water before use. 100 ml up to 100 m² · 200 ml up to 200 m² · 500 ml up to 500 m² · 1 L up to 1,000 m².

Dilution rate: 1–2 ml/m², diluted in 30–50 ml of water per m² (10–20 L/ha in 300–500 L water).

Not sure how big your lawn is? Measure your lawn and pick the bottle that covers it.
Good to know
  • ✓Goes on with a knapsack sprayer or watering can
  • ✓Suitable for fast colour, hardening turf & checking moss
  • ✓Keep children and pets off the lawn until the treated grass is dry
  • ✓Apply in year-round

UK-made liquid concentrate · dilute & spray

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A concentrated 6% liquid iron for lawns that deepens grass colour fast, hardens turf for autumn and winter and checks moss - with no nitrogen, so no soft growth to mow off.

Coverage, dilution & analysis

Coverage & dilution

Coverage
100 ml up to 100 m² · 200 ml up to 200 m² · 500 ml up to 500 m² · 1 L up to 1,000 m²
Application rate
1–2 ml/m², diluted in 30–50 ml of water per m² (10–20 L/ha in 300–500 L water)
Season
Year-round

Analysis

NPK 0-0-0 + 6% Fe

  • Iron fertiliser solution based on ferrous sulphate (UK fertiliser)
  • Total iron (Fe) soluble in water 6% w/v
  • Water-soluble iron (Fe) 6% w/v
  • Nitrogen (N) 0% · Phosphorus pentoxide (P₂O₅) 0% · Potassium oxide (K₂O) 0%

Colour without the growth spurt

Most quick green-ups are really nitrogen feeds: the lawn goes green because it's growing hard, and you pay for it with the mower a week later. Iron works differently. Grass uses iron to make chlorophyll, so topping it up deepens the colour of the leaves you already have. Iron Sward Liquid has no nitrogen in it at all - it's a straight 6% iron solution based on ferrous sulphate - so you get the deep green without the soft, sappy growth that invites disease and extra cutting.

A liquid works on the day you apply it

A granule has to sit on the surface, take on moisture and break down before the grass gets anything from it. Diluted and sprayed, a liquid iron for lawns goes straight onto the leaf and into the top of the soil, so it's working from the day you put it on rather than waiting on the weather. That makes it ideal for a target date - a party, a viewing, the first weekend the garden's back in use - and easy to fit between your seasonal feeds.

Tougher turf for autumn and winter

Iron is the greenkeeper's autumn and winter tool. Ferrous sulphate toughens the leaf, helps the sward stand up to cold, wet weather and foot traffic, and blackens moss - which is why turf managers use it to harden turf as growth slows. On a home lawn, that means a light iron application in late autumn and again in winter keeps colour when everything else has gone dull, and knocks moss back before it takes hold in spring. Just keep it off paving and stone: it will stain.

When a shot of iron is the right call

Pale, washed-out grass that's already been fed and still looks tired. A patchy, mossy shaded corner. A lawn you want looking its best for a weekend. The week before an autumn scarify, to weaken the moss first. Or simply a couple of lighter, more frequent applications through the season instead of one big hit. Iron Sward Liquid covers all of those from one small bottle - and because you only mix what you need, the rest keeps for next time.

Why Mowd?

Concentrated, not watered down

A little goes a long way - one small bottle treats a whole lawn, so you are not paying to ship water around the country.

Straight to work

Diluted and sprayed, it reaches leaf and rootzone the same day rather than waiting on rain to break granules down.

Made by turf pros

Built on 40+ years of sports and domestic turf experience, blended and bottled in the UK.

Help when you need it

Plain-English guidance, the free MyLawn app and UK-based support if you ever get stuck.

Ready to give your lawn a lift this autumn?

Choose the bottle size that covers your lawn, dilute, and spray.

Frequently asked questions

What is liquid iron for lawns and what does it do?
Liquid iron is a concentrated iron solution you dilute in water and spray onto the grass. Iron Sward Liquid is 6% iron (Fe) based on ferrous sulphate. Grass uses iron to make chlorophyll, so it deepens the green colour of the leaf, toughens the sward and checks moss - without the flush of soft growth you get from a nitrogen feed.
How much liquid iron do I need for my lawn?
The label rate is 1-2 ml of concentrate per square metre, diluted in 30-50 ml of water per square metre. At the standard rate a 100 ml bottle treats up to 100 m², the 200 ml up to 200 m², the 500 ml up to 500 m² and the 1 litre up to 1,000 m². Use the higher rate where moss is the target and halve those coverage figures.
How do you apply liquid iron to a lawn?
Shake the bottle, measure out 1-2 ml for every square metre you're treating, and dilute it in 30-50 ml of water per square metre - so a full 100 ml bottle goes into 3-5 litres of water. Apply evenly with a knapsack or pressure sprayer on a still, dry day, ideally after mowing. Keep the spray off paths, patios and stone, because ferrous sulphate stains hard surfaces.
When should I put liquid iron on my lawn?
It's suitable for use all year round while the grass is growing. Use it in spring and summer for a quick green-up between feeds, and in autumn and winter to harden the turf and check moss. Avoid applying to frozen, waterlogged or drought-stressed grass, or in direct hot sun.
How often can I apply liquid iron to my lawn?
Little and often works best. A light application every four to six weeks through the growing season keeps colour topped up, with a stronger autumn application if moss is the problem. Don't exceed the label rate - more iron doesn't mean greener grass, and heavy doses can blacken the leaf temporarily.
Does liquid iron kill moss?
Ferrous sulphate is damaging to moss, so an application at the top of the label rate will blacken it and check its spread. Iron Sward Liquid is sold as an iron fertiliser rather than a dedicated moss killer, so for a heavy moss problem pair it with scarifying and fix the cause - shade, compaction or poor drainage - or use our granular Iron Sward Moss Killer & Lawn Green-Up.
Is liquid iron safe for children and pets?
Keep children and pets off the lawn until the treated grass is completely dry. The concentrate is harmful if swallowed and irritates skin and eyes, so wear gloves and eye protection when mixing and spraying, wash hands afterwards, and store the bottle upright, out of reach and away from frost.
Will liquid iron stain my patio or paving?
Yes - ferrous sulphate will stain paths, patios, stone and decking rust-brown, and it's very hard to remove. Keep the spray strictly to the grass, don't apply on a windy day, and rinse any drips off hard surfaces with plenty of water straight away.

See all FAQs →

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