The Best Moss Killers For Lawns
Six granular and liquid treatments that turn lawn moss black so you can rake it out and let the grass take over.
Our quick verdict
Our pick of the best moss killer for lawns is the Miracle-Gro Evergreen Complete 4-in-1, which kills moss and weeds and feeds a hungry lawn in one pass from a spreader. It was very effective on moss in our testing. For a large lawn, go for the A1 Lawn Double Strength, where the 10kg and 20kg bags keep the cost of each application down.
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Our Picks At A Glance
- Check price of Miracle-Gro Evergreen Complete 4-in-1
Best Overall
Miracle-Gro Evergreen Complete 4-in-1Most lawns that need moss killed alongside weeds and a feed
- Check price of Pro-Kleen Iron Sulphate Moss Killer
Best Liquid Formula
Pro-Kleen Iron Sulphate Moss KillerLarge lawns treated with a sprayer on a tight budget
- Check price of MOOWY Iron+ 2-in-1
- Check price of A1 Lawn Double Strength
- Check price of Maxicrop Moss Killer & Lawn Tonic
Best Liquid Runner-Up
Maxicrop Moss Killer & Lawn TonicSmall to medium lawns treated with a watering can
- Check price of Miracle-Gro EverGreen Premium Plus
Best Organic
Miracle-Gro EverGreen Premium PlusLawns near paths and patios where staining is a worry
Lawn size and what sits around the grass will steer you between granules and liquid. Iron sulphate liquids are cheap per square metre on a big lawn, but they need a sprayer and mark any paving they land on, so a lawn edged by a patio suits a granular or organic feed instead. The all-in-one granules cost more because they feed the grass and tackle weeds in the same pass.
Treating moss is part of the routine on our own lawn and at our rentals. The six below cover granular feeds, liquid iron sulphate and an organic no-rake option.
How We Tested These Lawn Moss Killers
Keeping moss under control is part of the routine on our own lawn and on the gardens we look after at our rentals and Airbnbs. Some of those lawns had just the odd mossy patch and others were badly affected, so we've used a range of formulas on very different starting points.
Each one was judged on how well it killed the moss, how easy it was to apply, how quickly the results showed and any extra benefits such as greener grass. We've spread granules by hand and with a spreader.
A spreader is worth buying if you treat a lawn every year. It's much quicker than throwing granules by hand, and it puts the product down evenly, which matters because an overdosed strip can scorch the grass. The short video below shows us running one up and down a lawn.
Using A Garden Spreader To Apply Moss Killer To Your Lawn Is Easier & Ensures An Even Distribution!
Results are easy to judge, because whatever the treatment kills turns black or brown while the grass around it stays green. The before and after photos below come from one of our treated lawns, where the problem was mostly low weeds rather than moss.
We keep trying new formulas as brands improve them, and where we've relied on a brand's figures for coverage or feeding time, we've said so. Beyond the results on the grass, safety round children and pets, coverage and what each pack costs for the area it treats all fed into the final order.
The Best Lawn Moss Killers We Recommend
The list includes granules for a spreader and liquids for a watering can or sprayer. Check the dose rate on the pack before you start.
Best Overall
Miracle-Gro Evergreen Complete 4-in-1
Best for: Most lawns that need moss killed alongside weeds and a feed
Check Price On AmazonEverGreen Complete 4-in-1 does four jobs in one pass, feeding the lawn, killing moss, killing weeds and thickening the grass. It was very effective in our testing, and it's the product in our spreader photo.
Miracle-Gro promises visibly greener grass in 7 days, and its Water Smart formula is designed to help the lawn cope with heat. Bags come in a range of sizes, the largest covering lawns of up to 500 square metres, so you can match the bag to your garden.
A spreader gives the most even result, though you can spread it by hand with gloves on. Expect the moss and weeds to go purple, brown or black before they die off, which leaves the lawn looking worse for a short while until fresh grass fills in.
What we like
- Very effective on moss in our testing
- Kills moss and weeds while feeding the lawn
- Visibly greener grass in 7 days according to Miracle-Gro
- Bag sizes for lawns up to 500 square metres
- Water Smart formula to help in hot weather
- Works well through a spreader for an even finish
What to know
- Treated areas turn purple or brown until new grass grows back
Our verdict
Moss, weeds and a hungry lawn tend to turn up together, and EverGreen Complete 4-in-1 sorts all three with one trip up and down the lawn. It's the product we'd put down first on most lawns, though A1 Lawn Double Strength works out cheaper on a big one. Miracle-Gro advises applying it between April and September, so time it for a cool, damp spell in that window.
Best Liquid Formula
Pro-Kleen Iron Sulphate Moss Killer
Best for: Large lawns treated with a sprayer on a tight budget
Check Price On AmazonPro-Kleen is a professional-grade iron sulphate that you dissolve in water and spray over the lawn. Iron sulphate is the classic moss treatment, killing moss quickly and giving the grass a dark green colour at the same time.
Pro-Kleen says its formula covers twice the area of standard iron sulphate products, with 2.5kg treating roughly 2,500 square metres. Tubs run from 1kg to 10kg with a resealable lid.
It can go on wet or dry lawns, with the dose rates printed on the tub. You'll need a pump sprayer or watering can, since it can't be used straight from the tub. Keep it off paths and patios too, as iron sulphate leaves rusty stains on stone and concrete.
What we like
- Around 2,500 square metres from 2.5kg according to Pro-Kleen
- Tubs from 1kg to 10kg with a resealable lid
- Works on wet or dry lawns
- Turns grass a strong dark green
- Dose rates printed on the tub
What to know
- Has to be diluted and applied with a sprayer or can
- No added lawn feed beyond the iron
Our verdict
Coverage is the reason to buy Pro-Kleen, and the brand quotes around 2,500 square metres from a 2.5kg tub. That makes it a strong choice for a big lawn, provided you're happy to mix and spray. If you'd rather spread granules, Miracle-Gro EverGreen Complete 4-in-1 is simpler to apply.
Best Fast-Acting
MOOWY Iron+ 2-in-1
Best for: Small lawns where you want quick visible results
Check Price On AmazonMOOWY Iron+ is built for speed. The brand says you'll see greener grass within two days and moss dying off in less than a week, which suits anyone who wants to see a difference quickly.
The granules are good quality, and the bag reseals so you can store what's left without waste. Detailed instructions come with it, which helps if it's your first time treating moss.
MOOWY backs the product with a money-back guarantee. Per square metre, it's the most expensive moss killer in this roundup, so it makes most sense on a small or medium lawn.
What we like
- Greener grass in two days according to MOOWY
- Moss dying back in under a week
- Good quality granules
- Resealable bag to avoid waste
- Money-back guarantee from MOOWY
- Clear instructions supplied
What to know
- Most expensive moss killer per square metre in this roundup
Our verdict
Speed is what you pay for with MOOWY Iron+, and it's the most expensive per square metre in this list. On a small lawn that extra cost stays modest, and the money-back guarantee takes some of the risk out of trying it. A large lawn is a different matter, where A1 Lawn Double Strength costs less per square metre.
Best Value
A1 Lawn Double Strength
Best for: Large lawns that need regular feeding with moss and weed control
Check Price On AmazonA1 Lawn is a UK lawn specialist, and the same brand behind the highly rated seed in our guide to the best grass seeds for UK lawns. Its Double Strength moss killer comes in 10kg and 20kg bags, which makes it excellent value for anyone with a large lawn.
As well as killing moss, it feeds the lawn and kills weeds, with a high nitrogen and iron content to green the grass up. The formula is made for UK conditions and certified by DEFRA, FERA and SASA.
The feed lasts around 6 weeks, which is shorter than the 3 months Miracle-Gro quotes for EverGreen Premium Plus, so plan on treating more frequently through the growing season.
What we like
- Large 10kg and 20kg bags
- Kills moss and weeds and feeds the lawn
- High nitrogen and iron content
- Certified by DEFRA, FERA and SASA
- Made by a UK lawn specialist for UK conditions
What to know
- Feeds for around 6 weeks, shorter than EverGreen Premium Plus
- No small bags for a tiny lawn
Our verdict
A1 Lawn Double Strength is the pick for a large lawn that you feed and treat regularly through the year. The big bags make it cheap per application. On a small lawn, the bags are more than you need, so Miracle-Gro EverGreen Complete 4-in-1 in a smaller size is the better buy.
Best Liquid Runner-Up
Maxicrop Moss Killer & Lawn Tonic
Best for: Small to medium lawns treated with a watering can
Check Price On AmazonMaxicrop mixes ferrous sulphate with seaweed extract, which sets it apart from the other treatments here. The iron kills the moss while the seaweed acts as a tonic for the grass, giving a greener lawn alongside the moss control.
It's a liquid that mixes easily with water and goes on with a watering can or sprayer, so there's no spreader to buy. Maxicrop says a 2.5 litre tub treats around 166 square metres.
That coverage is low next to Pro-Kleen, and Maxicrop is relatively expensive compared with other liquid moss killers. It's a better fit for small and medium lawns than large ones.
What we like
- Seaweed extract tonic in the formula
- Ferrous sulphate for moss control
- Mixes easily with water
- Goes on with a watering can or sprayer
- Greens the grass up
What to know
- Only around 166 square metres from 2.5 litres according to Maxicrop
- Costs more per square metre than Pro-Kleen Iron Sulphate
Our verdict
The seaweed tonic is what makes Maxicrop different, and it's a good match for a smaller lawn where a watering can is all you want to use. The low coverage per tub rules it out for big lawns, where Pro-Kleen Iron Sulphate goes much further.
Best Organic
Miracle-Gro EverGreen Premium Plus
Best for: Lawns near paths and patios where staining is a worry
Check Price On AmazonEverGreen Premium Plus is Miracle-Gro's No Rake formula, which the brand describes as organic and designed to reduce moss coming back. Miracle-Gro says it gives greener grass in 7 days and keeps feeding the lawn for up to 3 months, with extra magnesium for colour.
Two practical points stand out. It won't stain paths or patios beside the lawn, unlike iron sulphate, and Miracle-Gro says it's child and pet friendly once watered in. It goes on by hand with gloves or with a spreader, and comes in sizes covering 50, 100 or 200 square metres.
In our testing, the moss killing results were very close to the cheaper Complete 4-in-1, so the extra cost buys the longer feed and stain-free formula.
What we like
- Won't stain paths or patios next to the lawn
- Feeds for up to 3 months according to Miracle-Gro
- No Rake formula aimed at reducing regrowth
- Extra magnesium for greener grass
- Child and pet friendly once watered in
- Spread by hand or with a spreader
What to know
- Moss killing was very similar to the cheaper Complete 4-in-1 in our testing
Our verdict
EverGreen Premium Plus is worth buying if your lawn runs right up to a patio or light paving that you don't want stained, or you want the longest-lasting feed. For moss killing alone, Miracle-Gro EverGreen Complete 4-in-1 gave us similar results for less, and A1 Lawn Double Strength is better value on a big lawn.
Choosing A Moss Killer For Your Lawn
A lawn moss killer can clear moss in around a week, but which one suits you depends on the size of the lawn, how you want to apply it and what else you'd like it to do. Granules, liquids and organic formulas all work, and the sections below cover what separates them.
Why Moss Takes Hold
Moss is a sign that the grass isn't growing well. These are the conditions where it spreads most:
- Wet or waterlogged ground with poor drainage
- Grass stressed by drought or cut too short
- Worn areas with heavy foot traffic
- Shade beneath trees or beside tall fences
- Poor, acidic or compacted soil
A moss killer clears what's there, but it'll come back unless you deal with the cause. Weeds tend to move in under the same conditions, as the photo below shows.
Where weeds are the bigger problem, our pick of the best weed killers for every part of the garden covers lawn-safe options.
Granules Or Liquid
Granular products such as the Miracle-Gro and A1 Lawn feeds go down with a spreader or by hand and are the easiest to apply evenly. Liquids such as Pro-Kleen and Maxicrop are mixed in a watering can or pump sprayer and work quickly, and iron sulphate in particular is cheap per square metre. The trade-off with iron sulphate is staining, so keep it well away from paving, and if it does mark a path, our guide to cleaning patio slabs has the fix.
When To Treat Moss
Between April and September is the main window for moss killers in the UK, with spring treatment hitting moss before it spreads its spores in summer. Apply in cool, damp weather and avoid hot, dry spells, as moss killers can scorch stressed grass. Follow the dose rate on the pack exactly, since too little won't kill the moss and too much can burn the lawn.
Raking Out And Reseeding
Give the treatment time to work, which is around 7 days for most products, and wait until the moss has turned black or brown. Then rake out the dead moss or run over the lawn with one of the best lawn scarifiers. Bare patches left behind are the perfect spot for fresh seed, and keeping the new grass watered with a garden sprinkler helps it fill in before moss can return.
Children, Pets And Coverage
Freshly applied moss killer can be harmful to children and pets, so keep them off the lawn for as long as the pack says. Some brands say up to 5 days, while others say the lawn is safe once the product has been watered in.
Coverage is always given in square metres, which is the fairest way to compare value between products sold in very different bag and tub sizes. Measure your lawn first, then pick the pack that covers it with a little to spare.
Lawn Moss Questions We Get Asked
How long does lawn moss killer take to work?
Most lawn moss killers start to work within a few days and turn the moss black or brown in around 7 days. Iron sulphate liquids act quickest, while granular feed and moss products take a little longer. Wait until the moss is clearly dead before raking or scarifying it out, otherwise you'll spread live moss around the lawn.
Do you have to rake out dead moss after using moss killer?
Yes, raking out dead moss is important for most products, because the dead layer blocks light and stops new grass filling the gaps. Use a spring-tine rake on a small lawn or a scarifier on a larger one. Some no-rake formulas, such as Miracle-Gro EverGreen Premium Plus, are designed to break down without raking.
Will moss killer kill the grass?
Lawn moss killer won't kill healthy grass if you use it at the right dose. Grass can blacken or scorch if you overdose, apply it in hot, dry weather or spread it unevenly so some strips get a double helping. Using a spreader and following the pack's dose rate keeps the grass safe while the moss dies off.
Is iron sulphate safe for pets?
Iron sulphate is safe for pets once it has been watered in and the lawn has dried, but keep dogs and cats off while it's wet or still sitting on the grass. It can irritate skin and paws and stains anything it touches. Check the guidance on the tub for the exact waiting time before letting pets back out.
Is Miracle-Gro EverGreen Premium Plus worth paying more for than the Complete 4-in-1?
Only if your lawn runs up to a patio or light paving, or you want the longer feed. In our testing the moss killing results were very close to the cheaper Complete 4-in-1. The extra cost buys a stain-free formula and a feed that Miracle-Gro says lasts up to 3 months.
Will iron sulphate stain my patio or paths?
Yes, iron sulphate leaves rusty stains on stone and concrete, so keep Pro-Kleen Iron Sulphate off paths and patios. Spray carefully along the lawn edge and don't let the mixture splash onto paving. If your lawn borders light paving, Miracle-Gro EverGreen Premium Plus is the one that won't stain it.
Is MOOWY Iron+ worth the extra money for speed?
On a small lawn, yes, because the extra cost stays modest. MOOWY says you'll see greener grass within two days and moss dying off in under a week, and it offers a money-back guarantee. It's the most expensive moss killer per square metre in our list, so a large lawn is better treated with A1 Lawn Double Strength.
Do I really need a spreader to put down granular moss killer?
A spreader isn't essential, but it's worth buying if you treat your lawn every year. It's much quicker than throwing granules by hand and gives the most even result with Miracle-Gro EverGreen Complete 4-in-1. You can spread by hand, though, as long as you wear gloves and follow the dose rate on the pack.
Our Choice Of Lawn Moss Killer
Miracle-Gro EverGreen Complete 4-in-1 is the moss killer we'd use on most lawns, as one pass with a spreader handles the moss, the weeds and the feed, and it worked very well on moss in our testing. For a big lawn on a budget, Pro-Kleen Iron Sulphate covers the most ground for the money.
A1 Lawn Double Strength is the best value granule for large lawns, and EverGreen Premium Plus suits lawns beside paving you don't want stained.
Archie is our gardening specialist. He started out as an apprentice at a gardening firm, built up his own knowledge from there and now writes most of our garden content.