• MowdBoost Sea of Green Liquid organic seaweed concentrate, 100ml bottle
  • MowdBoost Sea of Green Liquid organic seaweed concentrate, 200ml bottle
  • The full MowdBoost liquid lawn treatment range: Sea of Green, Soak and TerraCharge in 100ml and 200ml bottles
  • Sea of Green Liquid organic seaweed concentrate for lawns, 100 ml label showing analysis and application rate
  • Sea of Green Liquid seaweed concentrate 200 ml label covering up to 500 m² of lawn
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Sea of Green Liquid

Sea of Green Liquid

Spring to autumn · liquid concentrate

Organic seaweed, in liquid form

£9.95
£9.95
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  • ✓Improves soil fertility and nutrient uptake
  • ✓Helps grass shrug off drought and heat stress
  • ✓Stimulates germination and improves aeration
  • ✓Feeds the beneficial micro-organisms in your soil
Size

A concentrate — dilute with water before use. 100 ml up to 250 m² · 200 ml up to 500 m².

Dilution rate: 0.4 ml/m², diluted in 30–50 ml of water per m².

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 soil health, stress tolerance & natural colour
  • ✓Keep children and pets off the lawn until the treated grass is dry
  • ✓Apply in spring to autumn

UK-made liquid concentrate · dilute & spray

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An organic liquid seaweed concentrate that feeds the soil life under your lawn and helps grass handle drought, heat and heavy use.

Coverage, dilution & analysis

Coverage & dilution

Coverage
100 ml up to 250 m² · 200 ml up to 500 m²
Application rate
0.4 ml/m², diluted in 30–50 ml of water per m²
Season
Spring to autumn

Analysis

NPK 0-0-0.6 (+4% organic matter)

  • Organic seaweed extract (17 amino acids, plant growth hormones, carbohydrates and trace elements)
  • Organic matter 4%
  • Nitrogen (N) 0% · Phosphorus pentoxide (P₂O₅) 0%
  • Potassium oxide (K₂O) 0.6% (0.5% K)
  • pH 4.5

Seaweed has fed coastal soils for centuries

Farmers living by the sea worked seaweed into their land long before anyone talked about biostimulants. They could see what it did: better soil, better crops, plants that shrugged off a rough season. Sea of Green Liquid is that same idea in a bottle - a cold-processed seaweed concentrate you dilute and spray, packed with amino acids, natural plant growth hormones, carbohydrates and trace elements.

It works on the soil, not just the grass

Most of what makes a lawn look good happens out of sight. Seaweed extract feeds the micro-organisms living around the roots, and a busy soil releases nutrients your grass can actually use. That is why seaweed pairs so well with a granular feed - the feed supplies the nutrients, the seaweed helps your lawn get more out of them.

It also helps grass handle a hard summer. Seaweed stimulates the plant's own response to stress, so a lawn under drought, heat or heavy use has more in reserve.

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

How often should I apply liquid seaweed to my lawn?
Every four to six weeks through the growing season - roughly March to October. It is a gentle product, so a little and often beats one big soaking. Skip it when the grass is dormant or the temperature is below freezing.
Is liquid seaweed a fertiliser?
No. The analysis is 0% nitrogen, 0% phosphorus and 0.6% potash, so it is a soil conditioner and biostimulant rather than a feed. Use it alongside your seasonal granular fertiliser, not instead of it.
Can you put too much liquid seaweed on a lawn?
It is very forgiving, but there is no benefit in going heavier than the rate on the pack. Stick to 0.4 ml per square metre and put the extra effort into even coverage instead.
When is the best time of day to spray it?
Early morning or evening, straight after mowing, when the sun is off the lawn. Do not spray in direct sun or in hot weather. Mix only what you need and use it within three days.

See all FAQs →

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