Last updated on March 23rd, 2023
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My Best Moss killer for Lawns review looks at the pros and cons of each of the products I present and discuss the best features of each, some of them do more than just kill the moss, in fact, they pretty much all do by the very nature. I also recommend in which situations to use each product because some are easier to use to help avoid burning your lawn, which is a common mistake people make when applying moss killers.
My Buyer’s Guide discusses moss killers, how and when to use them and gives some tips for avoiding the problem of moss patches.
My Best Pick is Ferromel 20 Iron Sulphate Lawn Conditioner, Lawn Feed & Moss Killer. This lawn product contains 20% iron and makes short work of moss as well as conditioning your lawn to make it stronger. This is amazing stuff and is what I’m pictured with above but the packaging does sometimes vary, not sure why it just does. This is ideal if you have a large lawn and will help bring the cost down.
My Runner-up, the Pro-Kleen Premium Iron Sulphate Lawn Tonic/Lawn Conditioner & Moss Killer is another multi-purpose lawn product that kills moss. As already mentioned, it’s the same product as my best pick and is iron sulphate but this product comes in a resealable 2.5kg container which makes it a good choice for those with smaller lawns.
Below I have my main two best picks, these are what I personally use myself. They are both essentially the same product but one is what the professionals use in large bags so it’s more affordable per kg and sold by its chemical name and the other is marketed in a fancy tub designed for retailers in much smaller amounts. Something else to note, you only need a very small amount per square meter, I usually apply 10g per square metre to kill moss but then use it as a lawn tonic over summer to keep the lawns looking lunch and green. You can also use it on lime hating plants as a feed too.
First, a couple of things you need to know. Ferrous sulphate is by far the best moss killer available. I’ve used it for over 20 years and it’s what the professionals use. It’s important to know that it is sold under many names including Iron Sulphate, Sulphate heptahydrate and sulphate or iron amongst a few other names. It’s also important to know it comes in different grades including powder form which is what I recommend and crystal form. Generally, the best iron sulphate has an iron (Fe) content of 20%.
The reason it’s so effective is that moss cannot survive where iron is present but grass absolutely loves it. This means it can be used to kill the moss but also has a lawn feed/tonic and it gives the grass a lovely dark green lush effect too.
The top 4 best moss killers for lawns which have been included in our review are listed below:
- Ferromel 20 Iron Sulphate PREMIUM Lawn Conditioner, Lawn Feed & Moss Killer – BEST PICK
- Pro-Kleen Premium Iron Sulphate Lawn Tonic/Lawn Conditioner & Moss Killer – RUNNER UP
- EverGreen Complete 4-in-1 Lawn Care – Great for using with a spreader
- Maxicrop Moss Killer + Lawn Tonic
Top 4 Recommended Moss Killer For Lawn Reviews
1. Ferromel 20 Iron Sulphate PREMIUM Lawn Conditioner, Lawn Feed & Moss Killer
The Ferromel 20 Iron Sulphate Premium Lawn Conditioner & Lawn Feed comes in a large 25kg bag and is what I have always used for years. I have noticed over the years the packaging does change which is why the picture above may look different from a picture on a retailer’s website such as amazon for example. Not sure why, it’s the same company and product. This time it was even labelled as Ferrogranul 20 on the bag instead of Ferromel 20. It’s just good to know so you don’t think you received the wrong product.
Anyway, with almost 20% iron, it is perfect for promoting stronger turf growth and greener grass while being very effective at killing moss.
The picture below shows a close up of a section of lawn before I applied Ferrogranul 20, full of moss.
The second picture below is after only a few hours after spraying with Ferrogranul 20 iron sulphate. In a few weeks the grass will also greatly improve but it gives you an idea of how effective it is a killing moss.
There are a couple of days to apply iron sulphate to your lawn, the two easiest ways are using a garden sprayer as I usually do or by using a watering can which is easy enough on a small lawn.
You can use a spreader but I wouldn’t recommend it as it’s difficult to do accurately as it’s so fine. If using a sprayer which I recommend, especially on a larger lawn, you need to use 5-10g per square meter, or 3-5g per square meter if you want to use it as a lawn tonic to green up your lawn once you killed the moss off.
How to spray with a spayer
Basically, the easiest way is you measure out 5-10g (I usually use 10g) per litre of water to treat 1 square meter. For example, my Hozelock backpack sprayer is 16 litres full so I mix 160g (10g x 16 litres) of iron sulphate with 16 litres of water and spray an area of 16 square meters as evenly as possible. If you have a 10-litre sprayer, you could mix 100g of iron sulphate with 10 litres of water and spray over 10 square meters.
I also recommend mixing the sulphate of iron in lukewarm water as it dissolves better and then pouring this into your sprayer and topping up with cold water.
How to increase the concentrate to treat more area with less water
If you have a very large area to spray, this will take a long time so another way to do this is to use a much higher concentration of iron sulphate per litre of water. To do this, you would be best filling your sprayer with just water and spraying your lawn and seeing how many square meters it covers. If you are able to spray, for example, 50 square meters with a 5 litre sprayer, you would mix 10g x 50 square meters of iron sulphate (500g) with 5 litres of water and spray over 50 square meters. This way you are still applying 10g per square meter of lawn.
Applying with a watering can
So on small lawns, one of the best and easiest ways to apply iron sulphate is with a watering can. Simply get a 10 litre watering can or whatever size you have to hand with a fine rose. Mix 10g of iron sulphate per litre of water. With a standard 10 litre watering can, thats 100g of iron sulphate mixed with 10 litres of water over an area of 10 square meters. If you run out of water before covering the 10 square meters, don’t worry, refill again and carry on where you stopped.
Alternatively, use it in its dry state using a lawn spreader by hand, though you may burn your lawn with this method, so be careful. Some spreaders do not spread it very well because it is so fine.
Trusted by professionals and home users, this moss killer covers 2,500m2 maximum for greening purposes and 12,000m2 for moss killing if you use a stronger concentrate.
Just a couple of final thoughts on what ratio to use for mixing, you will find lots of recommendations from 5g per square meter to as much as 50g. From experience, I can tell you that 10g per square meter gives great results for killing moss and greening up lawns.
I would also recommend scarifying your lawn afterwards like I do to remove all the dead moss and help aerate the soil. If you had a bad infestation of moss this would also be a great time to overseed your lawn or areas of your lawn.
Here is a larger lawn I treated with Ferromel 20 iron sulphate and some before and after pictures. I increased the concentration per litre of water on this lawn but kept it to 10g per square meter.
To do this I measured the area in square meters, then I weighed 10g x the square meter. In this case about 160 square meters so I had 10g x 160 square meters which is a total of 1.6kg of iron sulphate. I then mixed this in a 16 litre backpack sprayer and applied it as evenly as possible over the whole lawn.
The picture below is after it was sprayed only a couple of days later, as you can see, the moss had turned black and is ready to remove by scarifying the lawn.
I then had to remove the moss so I used the Hyundai petrol scarifier which is also an amazing machine. There was a lot of moss so I decided it was easier to remove the collection box and rake it up afterwards and then do a once over with a lawn mower to collect any leftover moss.
And finally after collecting the moss from the lawn by raking it into piles and the final result.
Just a little word of warning, iron sulphate will stain flags with a brown rust colour so be careful not to get any on your patio. If you do, simply wash it down with water. You can also remove stains with a strong patio cleaner such as Smartseal Patio Clean Xtreme which I have also reviewed. I believe white vinegar or lemon juice can also remove the stains but have not tried this myself.
- Can be used as a moss killer or lawn conditioner according to your needs.
- Effective both when dissolved in water or spread in its dry state. (I recommend dissolving in water)
- Covers a wide area with only a small amount of iron sulphate.
- Trusted by professionals to maintain lawn health.
- Comes at an affordable price, especially when purchased in bulk.
Ferromel 20 Iron Sulphate Premium Moss Killer, Lawn Conditioner & Lawn Feed is a great product. Its versatility is that you can use it to green your lawn or to kill moss, and it can be applied dry or mixed with water and applied using a good garden sprayer or watering can.
Effective, affordable and multipurpose are some of the words that I would describe this product perfectly. After taking all this into consideration, I chose this as my Best Pick of the Lawn Moss Killers I present here because it’s just so effective and which is why the professionals swear by it including myself. If you only have a small lawn, the Pro-Kleen Premium Iron Sulphate is the same product just in a more manageable size and sold by a different brand. I review this one further down but it’s essentially the same product inside the tub so have included a link below too.
Compare the best prices from available sellers below
If you also have issues with moss on your patio, driveways or paths, check out my recommended moss killers to use here that doesn’t stain your patio.
2. Pro-Kleen Premium Iron Sulphate Lawn Tonic/Lawn Conditioner & Moss Killer
The Pro-Kleen Premium Iron Sulphate Lawn Tonic/Lawn Conditioner & Moss Killer is another option also used by professional landscapers to keep moss at bay and the grass green. As already mentioned, it’s actually the same product as Ferromel 20 Iron Sulphate PREMIUM Lawn Conditioner, Lawn Feed & Moss Killer, it’s just marketed in a fancy tub by a different brand which is why it’s my Runner-up.
Packed in a 2.5kg container, the ferrous iron moss killer can be used in its wet or dry form. However, to obtain the best results, use it wet which means using a sprayer a garden sprayer or watering can as explained earlier. For keeping the grass green, the 2.5kg unit will cover 2500m2 giving good coverage for large lawns but it’s still a small enough tub if you have a smaller lawn as it’s resealable.
On treating and killing moss, it will cover 500m2 and 1500m2 for turf hardening. Easy to use and store in a resealable container, this moss cleaner is effective and is one of the most popular moss killers I have used. As always, follow the instructions to get the expected results or use my recommendations which is 5-10g per litre of water per square meter for killing moss.
- Used for various lawn functions and comes in a resealable tub.
- Can be used in its dry form using a spreader or wet form in a sprayer, whichever works best for your lawn.
- Covers up to 500m2 when killing moss.
- Professional grade so results are guaranteed.
- Lacks a scoop for precise measurements.
The Pro-Kleen Premium Iron Sulphate Lawn Tonic/Lawn Conditioner & Moss Killer is an affordable moss killer and a great alternative to my best pick for those with small lawns who don’t have a need for a full 25kg of iron sulphate. I like that it can be used in both dry and wet forms depending on how you prefer to spread your lawn treatment, personally, I always recommend using a sprayer or watering can. Overall it’s just an easy to apply moss killer that works great and can even be used as a lawn tonic and a slightly less concreated dose.
Compare the best prices from available sellers below
3. EverGreen Complete 4-in-1 Lawn Care Bag
The EverGreen Complete 4-in-1 Lawn Care Bag gives you a thick green lawn at the same time as annihilating weeds and moss – a true multi-tasking product ideal for spring and autumn lawn care.
Sold in durable plastic 12.6kg bags, the compost-sized bags contain iron sulphate that is known to have the desired effect on moss. It relies on Watersmart technology to ensure the soil entraps water and nutrients, which is an added feature not found in other products.
This lawn treatment can be used in spring, summer or autumn. Be sure to keep children and pets away from the lawn at this time to prevent any harmful health effects. You can expect to see results in around seven days.
You will need a spreader, so if you don’t possess one, we suggest you get one. It will make the process a whole lot easier and keep your grass from burning because too much product spread in one area leaves the lawn with unsightly bald patches. If you’re not experienced, we don’t recommend spreading by hand. A lawn spreader is a must.
- Multi-tasks by thickening your grass, making it greener, killing off moss and weeds.
- Three-season use lets you care for your lawn throughout the growing season.
- Needs a spreader and a keen eye to facilitate equal product distribution.
The EverGreen Complete 4-in-1 Lawn Care Bag is a good choice if you have a large area of lawn to cover. It helps your grass grow greener and thicker, controls weeds, kills moss, it simply does it all. However, you need to carefully follow the provided instructions. Make sure to use a spreader and follow all the instructions provided.
Compare the best prices from available sellers below
4. Maxicrop Moss Killer + Lawn Tonic
The Maxicrop 2.5L Moss Killer + Lawn Tonic features a seaweed extract which is what makes it more unique, combined with the all-powerful ferrous sulphate for killing moss. This tonic is designed to be applied mixed into water, making it easy to apply and much less likely to burn the lawn.
Appropriate for home gardens, the 2.5L unit can be mixed with water within the recommended ratios to kill off the moss within an area of 80m2. Alternatively, you can use this product as a general feed when conditioning your garden to always look green.
The seaweed extract is the ingredient that is responsible for promoting greener growth. It also has 2% nitrogen to supply the soil with that much-needed nutrient. Keep this product away from your pets and children because it may cause skin irritation when wet but once dried it is perfectly safe.
- Mix with water to start killing the moss straight away.
- Features a seaweed extract that promotes the growth of greener grass.
- Easy to apply by watering can or sprayer (sprayer is more efficient).
- Results visible in a few days if your moss isn’t too thick.
- Budget-friendly and so good for domestic gardens, even those with large lawns.
The Maxicrop 2.5L Moss Killer + Lawn Tonic is a simple and affordable product that you can use on a sizeable home lawn. It takes care of two functions – keeping your lawn green and keeping the moss at bay. Overall it is a great option to consider, especially if you want something you can just mix with water and then water on.
Compare the best prices from available sellers below
What to consider when choosing a moss killer for your lawn
Having moss in your lawn can turn into a serious problem if you don’t address it quickly and in the correct way. This Buyer’s Guide gives advice and information on applying moss killers and using a scarifier or lawn rake to remove moss.
However, we would rather you never encounter the problem of a mossy lawn so we end by offering some preventative measures to avoid this problem in your garden.
Raking or scarifying whether using a rake or powered scarifier like I do is an easy method to remove moss if the growth is not widespread. However, raking your moss at the wrong time to remove it from the lawn just heightens the problem. You must rake in very early spring when the spores are dormant, otherwise, the spores spread and more moss starts growing. Or you can spread the moss killer before and after raking which is a much better way to remove moss without the risk of making the matter worse. If you have a heavy growth of moss, you must apply moss killer before raking or scarifying your lawn.
Most moss killers perform at least two tasks – killing the moss and fertilising the soil. One of the products we review, the EverGreen Complete 4-in-1 Lawn Care Bag, controls moss, kills weeds, feeds the lawn and improves water absorption. What harms the moss and weeds is good for your grass. It’s a win-win for you. Check each moss killer product to see what other lawn care tasks it does for you.
Most moss killers use Ferrous sulphate, a chemical containing iron. Ferrous sulphate causes the moss to go black by drawing out moisture but has some benefits for your lawn. It reduces the alkalinity of the soil and creates a better environment for grass growth; it fertilises the soil and reduces the chance of turf disease. The higher the concentration of iron in the moss killer, the better for your lawn and the worse for the moss. But be aware, that this chemical stains whatever surface it comes into contact with.
Most of the moss killers in this review are non-caustic and biodegradable, making them friendly to the environment, your kids and your pets. Always read the ingredients on the package or container to determine what the solution contains. Look for the “active ingredients” that tell you what the working chemicals are.
Always follow the instructions for how to apply your particular moss killer. The instructions will say either “dry” application or “wet” application or give you a choice of these methods.
For the most successful application of moss killer granules, mow your lawn and remove the clippings to expose all the low-growing moss. Your product instructions will recommend that you use a lawn spreader for this task, and so do we. Calculate the size of the area you want to cover and how much moss killer you need to do so. Pour that amount of granules into the spreader and adjust the setting of the spreader to what the instructions say.
Wait until the lawn is moist, perhaps early in the morning, and then walk up and down the lawn with the spreader, overlapping the tyre tracks from the previous pass. The photos on the package of moss killer may show an alternate way of covering the lawn, so be sure to check that out.
The drawback of applying the moss killer granules dry is that you may put down too much in one spot and end up burning the lawn. Be sure to close the spreader when you turn corners so you don’t distribute heaps of the granules at the end of each row.
You need to choose the concentration of the liquid solution you want to use on your lawn. The instructions on your moss killer container give you recommendations, follow the dilution instructions. For example, if the ratio you want is 1:1, mix 1 litre of the product with 1 litre of water. Many moss killer brands recommend using a watering can with a fine nozzle to spray the moss with this solution in order to better control its application. For small patches of green, a hand spray bottle is fine.
The drawbacks to a wet application are that you need to measure the solution carefully and add it to the right amount of water for the correct dilution; you need to spray the liquid evenly over the moss and lawn, and you have to be careful of the wind direction.
But don’t be put off by these drawbacks; just follow the instructions carefully and you should be OK.
When to treat moss
The best times to treat moss are in spring and autumn. As most moss killers also contain lawn fertilisers, this coincides with the right times to fertilise your lawn. In spring, treat the lawn in the latter half of March and lightly rake out the dead moss in early April. In autumn, apply the moss killer early in the season and then aerate the lawn, ready for winter.
While moss itself doesn’t harm your lawn, the conditions that encourage its growth do. Here’s what to look out for to prevent moss from taking over your lawn in the first place or to stop its return once you’ve painstakingly removed it.
Inadequate nutrients for the grass to feed on make lawns weak and unable to fight. Because moss is rather persistent, it is better if your soil is enriched to give the grass a fighting chance. Regular aeration, reseeding and fertilising are required.
Too much thatch encourages moss growth by shading it from the scorching sun and providing moisture for growth. Scarification is usually employed to get rid of excessive thatch and begin your lawn’s journey back to health.
Wet areas with poor drainage are likely to encourage the growth of moss. This is simply because moss needs a lot of water to be healthy and strong. If you need to, don’t hesitate to seek soil drainage options.
Compacted soil restricts the proper formation of deep roots. Grass with shallow roots has a lower chance of surviving and gives way to a wider moss infestation with its strong roots. Aerate your lawn at the proper times in the growing season.
Just our usual reminder to read all the safety precautions on the instructions and to follow them. You’re dealing with chemicals here and, even if they’re biodegradable, it’s better to wear gloves and a mask when mixing them up and applying them. And keep people, especially kids and pets, off the sprayed areas until the safety precautions tell you it’s safe to let them loose on the lawn again.
How can I prevent moss from returning to my lawn?
Moss thrives in conditions that harm your lawn; conversely, keeping your lawn healthy creates an environment in which moss can’t grow. You want to avoid having: too thick a layer of thatch between the grass blades and the soil; poorly fertilised soil; soggy areas of standing water; and soil that’s been packed down over time.
In summary, a regular lawn care regime of mowing, watering, and fertilising, with scarifying and aeration in the proper seasons will keep your lawn healthy and moss at bay.
Can I use a standard weedkiller on my lawn moss?
Many standard weed killers harm whatever vegetation they come into contact with. Even if you carefully select a weedkiller that leaves the grass alone, it probably won’t work on moss. Mosses are not like most other plants. They don’t have a central or root system that moves water and nutrients throughout them, so there’s nowhere for the weedkiller to circulate. Moss killers are designed for moss’ primitive structure and won’t harm grass.
Dealing with moss in your lawn needs discipline and patience, especially if you have recurring moss growth. The moss killers we review give you a good start in removing the moss. Practice safe lawn conditioning methods to encourage proper grass growth and keep the moss from coming back. The best soil conditions for growing a vibrant lawn are the worst conditions for moss to take root in.
Our Best Pick for moss killer for lawns is the Ferromel 20 Iron Sulphate 25KG PREMIUM Lawn Conditioner & Lawn Feed. This is a professional-grade product with almost 20% iron compound as the active ingredient.
Pro-Kleen Premium Iron Sulphate Lawn Tonic/Lawn Conditioner & Moss Killer is our Runner-up and is also a premium-grade moss killer. This product is ideal for those with small lawns or a minimal moss problem because it comes in a 2.5kg container that can be resealed.
We have reviews for the products you need to keep your lawn in its best condition so moss can’t take root there. Maybe you need a new electric mower or perhaps you prefer a petrol-powered mower. Take a look at the Top 7 Best Lawn Aerators as well as the Best Petrol Lawn Scarifiers. You may also need to consider draining parts of your lawn. Or perhaps you want to give your lawn some extra fertiliser.
Last update on 2023-11-20 / Affiliate links / Images from Amazon Product Advertising API