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Some lawns may encounter the troublesome challenge of moss growth due to poor growing conditions. Fortunately, addressing it is straightforward, and it’s achieved using a dedicated moss killer, with the optimal timeframe for treatment falling between April and September.
When choosing between the various formulas, each will provide a coverage measurement and dosage instructions for treating your entire lawn. Therefore, before purchasing any of the moss killers, you’ll want to measure your lawn in square metres to avoid coming up short.
To assist you in selecting a moss killer, our handpicked selection lists top-performing formulas, chosen based on our first-hand experience treating moss on an array of lawns that varied in terms of the amount of moss. Our testing (applied via hand, spreader and pump sprayer) and up-to-date research further ensure the quality of our recommendations.
Our Top Picks At A Glance:
Best Overall: Miracle-Gro Evergreen Complete 4-in-1
As we take great pride in our garden and those that we manage, we always try to keep the lawn free of moss and bring the best out of it. Therefore, as we maintain multiple lawns, we’ve had the pleasure of testing a range of formulas.
During testing, we analyse the effectiveness, ease of application, results as well as any additional benefits (greener grass). To ensure we thoroughly test the formulas, we apply them by hand and with a spreader (as shown below).
Archie Rich/DIY Works
Archie Rich/DIY Works
If possible, we strongly recommend investing in a garden spreader whilst applying a moss killer on your lawn. Not only is it much easier, but it also ensures that the product is evenly distributed on your lawn.
Below is a video that we posted on our YouTube channel that shows us testing a moss killer whilst applying it using a spreader.
When it comes to determining the success of a moss killer, it’s usually very clear. For example, in the below case study, you can clearly see that the moss has been killed without the grass being affected by the product.
Archie Rich/DIY Works
Archie Rich/DIY Works
To keep up our commitment to reviewing and testing the latest lawn moss killers (for this article), we are continually testing the latest offerings from top brands in the UK. This means that when we notice a brand has released a new and improved formula, we will attempt to buy it and put it to the test where applicable.
As well as our testing and experience using a range of moss killers, we also based our recommendations on the latest research and several factors. Some of the factors that we took into consideration included the formula’s effectiveness, coverage, ease of application, pet/child-friendly formulation, additional additives and value for money.
By far one of the most popular products on the market to treat moss on lawns is the Miracle-Gro 4-in-1. It’s a lawn feed and moss killer that kills moss and weeds but also promises greener grass in just 7 days.
Depending upon the size of your lawn, the brand offer bags suitable for lawns up to 500 square metres. In terms of applying the product to your lawn, you’ll need to use a spreader for the best results but you can manually spread it.
"Water Smart" formula that resists heat
Visibly greener grass in just 7 days
During testing, it was very effective
Available in a range of bag sizes to best suit your lawn's size
Offers relatively good value for the money
Promotes a thicker and healthier lawn
It'll turn areas of your lawn purple/brown until new grass grows back
Overall, if you want a quick and easy solution for killing moss on your lawn as well as providing many other benefits, this formula by Miracle-Gro is perfect. For the best results whilst using this moss killer, the brand state that you should spread it on your lawn between April and September.
2. Best Liquid Formula: Pro-Kleen Iron Sulphate Moss Killer
A popular choice for killing moss upon lawns is the Pro-Kleen formula. This is because ituses a professional-grade iron sulphatethat has twice the coverage when compared to standard formulas.
To use this moss killer, you’ll require a watering pump sprayer for the best coverage. The brand also states that 2.5 KG will approximately treat 2,500 square metres of lawn but you can purchase bigger tubs if required.
Superior quality and long lasting formula
Available in 1 KG to 10 KG tubs with a resealable lid
Can be applied to wet or dry lawns
Tried and tested for the best results
Encourages strong and dark green grass
Requires dilution and can't be used straight from the tub
Overall, the Pro-Kleen Iron Sulphate is a high-performing moss killer for lawns that provides excellent results. It’s easy to apply with the suggested dosage amounts listed on the tub and you can apply it to wet or dry lawns too.
If you require a fast-acting lawn moss killer, the MOOWY brand has the answer with its Iron+ formula. According to the brand, you’ll be able to see moss being killed off in less than a week and greener grass in two days.
Visible results in less than a week
High quality granules within the formula
Easy reseal bag so there is no wastage
100% money back guarantee
Supplied with detailed instructions
Most expensive moss killer for lawns per m2
Although expensive, the MOOWY Iron+ is a high-quality moss killer for lawns that certainly won’t disappoint. For complete peace of mind, the brand even provides a 100% money-back guarantee, which clearly shows how confident the brand is of its product.
A1 Lawn is a brand that specialises in anything lawn-based (as you can probably figure out from the brand name) and as with their highly-rated grass seeds, their moss killer also offers great value for the money. This is because it’s a double-strength formula that comes in large bags (10 or 20 kg) for tackling lawns of all shapes and sizes.
UK brand that develops its products for the UK climate
As well as killing moss, it also feeds the lawn and kills weeds
Formulation includes high nitrogen and iron content
Certified by DEFRA, FERA and SASA
Excellent value for the money
Compared to the alternatives, it doesn't feed the lawns for as long (6 weeks as opposed to Miracle-Gro's 3 months)
If you have a large lawn that you want to regularly feed and kill moss and weeds, the A1 Lawn’s formula is a great option to consider. Not only does it offer great value for the money but it’s also very effective too.
5. Best Liquid Runner-Up: Maxicrop Moss Killer & Lawn Tonic
The Maxicrop Moss Killer and Lawn Tonic is fairly unique because it includes a seaweed extract within its formula. It’s a liquid based application that’s suited to lawns of all sizes and it simply mixes with water in a watering can. According to the brand, a 2.5-litre tub can approximately treat 166 square metres with great results.
Easily mixes with water
Formula includes added ferrous sulphate
Quick and effective results
Makes grass greener
Application can be achieved in a sprayer or watering can
Relatively expensive when compared to other liquid moss killers
Although expensive when you consider the coverage, it does provide great results with such a simple application. The added seaweed extract also encourages the grass to grow greener and it’s a great addition that makes this formula stand out from the alternative lawn moss killers on the market.
6. Best Organic: Miracle-Gro EverGreen Premium Plus
Another moss killer by Miracle-Gro is theirlatest organic “No Rake” formula that promises to reduce moss regrowth, provide feed for 3 months and produce greener grass in just 7 days.
This particular formula is available in three different sizes that are suitable for 50, 100 or 200 square metres of coverage.
Desirable organic formulation
Extra magnesium for greener grass
No staining of paths or patios near the lawn
Children and pets friendly when watered in
Application by hand (wearing gloves) or a spreader
Results within just 7 days
Feeds the lawn for up to 3 months after application
During testing, as a moss killer, we felt that the results were very similar to the cheaper 4-in-1 formula recommended above
Although this organic moss killer is more expensive when compared to many of the alternatives, the hand application may be more suitable for some people. It also benefits from the fact that it doesn’t just act as a moss killer for lawns but also prevents regrowth and encourages greener grass.
Moss Killer Buying Guide
Lawns that are covered in moss aren’t aesthetically pleasing to look at, and they’ll eventually get worse. Luckily, a moss killer that’s designed for lawns can remove the moss in as little as a week.
They are available in a range of formulas that include organic ingredients to powerful iron sulphate. Application varies with liquid moss killers requiring a pump sprayer or watering can, whereas others can be applied by hand.
To help you make an informed buying decision, we have produced the guide below regarding moss killers for lawns.
What Causes Moss on the Lawn
Poor growing conditions are the main contributor to moss growing on your lawn, and some of the main areas of the lawn that suffer from moss include:
Wet and waterlogged areas
Worn areas with heavy foot traffic
Beneath trees or other shady areas
Infertile soil or acidic conditions
Using a moss killer that’s designed for lawns will remove the growth of moss, but it’s important that you also try and rectify the causes of the moss growing in the first place.
Archie Rich/DIY Works
When To Apply A Moss Killer To Your Lawn
Many professionals state that betweenApril and Septemberis the best time to apply a moss killer to your lawn. This is because moss produces spores, which are more common in spring and autumn. This means in April, you can target the moss just before it begins to spore in the summer months.
The application of the product depends upon the moss killer you are using because the dosage amounts differ. Some can also be used in wet or dry conditions and applied via a pump sprayer, watering can, spreader or by hand (using gloves).
It’s advised that youapply moss killers in cool damp conditions and avoid extremely dry or hot conditions.
It’s also critical that youfollow the dosage instructions closelybecause too little won’t be as effective, and too concentrated can scorch the grass.
After application, you will want to allow a specified period of time (usually 7 days) for the formula to get to work. Once the moss is visibly dead or has turned black, you can use a garden rake to collect the moss.
Pet & Children Friendly
Freshly spread moss killer on the lawn can be hazardous to children and pets. As witha weed killer, you will want to wait a specified amount of time before allowing your pets or children on the lawn. Some brands state that you should wait up to 5 days, whereas others state that it’s safe after it has been watered.
As most moss killers for lawns are available in multiple sizes, it can be difficult to judge which offers the best value for money. The coverage ismeasured in square metres, and this will allow you to see which formulas are best suited to your lawn size and if they are also good value for money.
To determine how much you will need, you can multiply the length and width of your lawn. This will then provide you with the lawn’s size in square metres and allow you to choose a suitable size moss killer.
Moss can ruin the appearance of your lawn, and if left untreated, it can become harder to remove. Therefore, tackling the problem sooner rather than later is highly recommended and using the latest moss killers that are designed specifically for lawns will allow you to effectively take action with results in as little as 7 days.
All of our recommendations listed within our roundup are suited to a range of budgets and can be applied in various methods to best suit your requirements. However, if you require further help with regards to our moss killer recommendations, feel free to get in touch and we will try to provide our assistance where possible.
Written By Archie Rich
With a robust background as an apprentice at a renowned gardening firm, Archie has blossomed into a self-made gardening specialist at DIY Works. His passion for cultivating thriving green spaces is matched only by his unwavering commitment to sharing expert advice and inspiring fellow gardening enthusiasts.