• MowdGrow Slow Release Liquid Feed 18-3-6 – slow release liquid lawn feed, 100 ml bottle on a white background
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Slow Release Liquid Feed 18-3-6 – Slow Release Liquid Lawn Feed

Slow Release Liquid Feed 18-3-6 – Slow Release Liquid Lawn Feed

Spring to early autumn · liquid concentrate

The liquid feed that keeps on feeding

£6.95
£6.95
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  • ✓Instant green-up, then weeks of steady feeding
  • ✓60% of the nitrogen is slow-release methylene urea
  • ✓Taken up through the leaf - works when granules are waiting for rain
  • ✓2.5 ml per m² - a 100 ml bottle feeds up to 40 m²
Size

A concentrate — dilute with water before use. 100 ml up to 40 m² · 200 ml up to 80 m² · 500 ml up to 200 m² · 1 L up to 400 m².

Dilution rate: 2.5–7.5 ml/m², diluted in 30–60 ml of water per m² (25–75 L/ha in 300–600 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 steady little-and-often feeding through the growing season
  • ✓Keep children and pets off the lawn until the treated grass is dry
  • ✓Apply in spring to early autumn

UK-made liquid concentrate · dilute & spray

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A liquid lawn feed with 60% slow-release nitrogen. 18-3-6 gives an instant green-up, then keeps feeding for weeks - spray it on from spring to early autumn, little and often.

Coverage, dilution & analysis

Coverage & dilution

Coverage
100 ml up to 40 m² · 200 ml up to 80 m² · 500 ml up to 200 m² · 1 L up to 400 m²
Application rate
2.5–7.5 ml/m², diluted in 30–60 ml of water per m² (25–75 L/ha in 300–600 L water)
Season
Spring to early autumn

Analysis

NPK 18-3-6 (60% slow-release N)

  • NPK fertiliser solution 18-3-6 (UK fertiliser)
  • Total nitrogen (N) 18% w/w (23.2% w/v) - ureic nitrogen 7.2% w/w, nitrogen from urea-formaldehyde (methylene urea) 10.8% w/w
  • Water-soluble phosphorus pentoxide (P₂O₅) 3% w/w (3.8% w/v)
  • Water-soluble potassium oxide (K₂O) 6% w/w (7.7% w/v)

Two feeds in one bottle

A straight urea liquid is all instant hit: the lawn greens up in days and drops off just as quickly. Slow Release Liquid Feed splits its 18% nitrogen two ways. Forty per cent is ureic nitrogen, taken up through the leaf within days for the quick green-up. The other sixty per cent is methylene urea, a slow-release form that breaks down gradually in the soil, so your lawn gets a steady trickle of feed for weeks after you spray. Even colour, steady growth, no surge and slump - and because the nitrogen isn't all available at once, there's far less risk of scorch.

Little and often, the greenkeeper's way

Greenkeepers feed fine turf with liquids, little and often, because it keeps colour and growth steady and lets them control exactly how much nitrogen goes on. The same approach works on a home lawn. Use Slow Release Liquid Feed every 6-8 weeks through the growing season as your main feed, or as a top-up between your granular spring and summer feeds when the colour starts to slip. Because you only mix what you need, the rest of the bottle keeps for next time - shake well, store upright, and it's good for two years.

Taken up through the leaf

A granular feed has to sit on the surface, take on moisture and break down before the grass gets anything from it - so in a dry spell it can sit there doing very little. A liquid is taken up through the leaf and the top of the soil, so it's working from the day you apply it, rain or not. That makes it the feed to reach for when the lawn has gone pale in a dry June, or when you want a result for a specific weekend. And unlike a granule, the dose is entirely in your hands: 2.5 ml per square metre for a routine feed, up to 7.5 ml when the lawn is really hungry.

How much, and how often?

The label rate is 2.5-7.5 ml of concentrate per square metre, diluted in 30-60 ml of water per square metre. For most lawns, start at 2.5 ml per m² - a 100 ml bottle feeds up to 40 m², the 200 ml up to 80 m², the 500 ml up to 200 m² and the litre up to 400 m². Go higher only for a pale, hungry lawn, and don't exceed the top rate. Feed from March to September while the grass is growing, every 6-8 weeks, and pair it with Sea of Green Liquid seaweed if you want to look after the soil as well as the grass.

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 a slow release liquid lawn feed?
It's a liquid lawn feed where part of the nitrogen is in a slow-release form. Slow Release Liquid Feed is an 18-3-6 NPK solution with 60% of its nitrogen as methylene urea, which breaks down gradually in the soil. You get the quick green-up of a normal liquid feed from the ureic nitrogen, plus weeks of steady feeding from the slow-release part - without the surge of soft growth a straight urea liquid causes.
How much liquid lawn feed do I need for my lawn?
The label rate is 2.5-7.5 ml of concentrate per square metre, diluted in 30-60 ml of water per square metre. At the standard 2.5 ml rate a 100 ml bottle feeds up to 40 m², the 200 ml up to 80 m², the 500 ml up to 200 m² and the 1 litre up to 400 m². Use the higher rate for a pale, hungry lawn and divide those coverage figures by three. Not sure of your lawn size? Use our Measure Your Lawn tool.
How do you mix and apply liquid lawn feed?
Shake the bottle well. Measure out 2.5 ml for every square metre you're feeding and dilute it in 30-60 ml of water per square metre - so a full 100 ml bottle goes into 1.2-2.4 litres of water to feed 40 m². Apply evenly with a knapsack or pressure sprayer, or a watering can with a fine rose, on a still day when the grass is dry and growing. If you're using a watering can you can use more water than the label minimum to make even coverage easier - it's the amount of feed per square metre that matters, not the amount of water.
When should I apply liquid lawn feed?
Any time the grass is actively growing, from spring through to early autumn - roughly March to September in most of the UK. Avoid frozen, waterlogged or drought-stressed grass, and strong sunshine, which can scorch wet leaves. Spring and summer are when it does the most good; by mid-autumn your lawn wants a low-nitrogen autumn feed instead.
How often should I feed my lawn with it?
Every 6-8 weeks through the growing season is a good rhythm for most lawns. Because 60% of the nitrogen is slow-release, one application keeps feeding for weeks, so you don't need to be out with the sprayer every fortnight. You can also use it as a top-up between your granular spring and summer feeds when the colour starts to slip. Don't exceed the label rate - more feed doesn't mean a greener lawn.
Is liquid lawn feed better than granular?
They're different tools. A granular slow-release feed gives a bigger dose that lasts 10-12 weeks and is the easiest way to feed a whole season in one go. A liquid is a lighter, faster dose you control precisely: it works in dry weather when granules are waiting for rain, greens up within days and suits little-and-often feeding. Plenty of people use both - a granular seasonal feed as the base, with a liquid to keep the colour topped up in between.
Do I need to water liquid lawn feed in?
No. It's taken up through the leaf and the top of the soil, so it works without watering in. Apply to dry grass and leave it - but avoid spraying if heavy rain is due within a few hours, as it can wash off the leaf before it's absorbed. Leave a day or two before mowing so the grass has time to take it up.
Is it safe for children and pets?
Keep children and pets off the lawn until the treated grass is completely dry. The concentrate causes serious eye irritation, so wear gloves and eye protection when measuring and mixing, wash your hands afterwards, and store the bottle upright, out of reach and away from frost. Once it's diluted and dry on the leaf, the lawn can be used as normal.

See all FAQs →

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