Best Moss Killer For Lawns in the UK: Granular, Liquid & Pet Friendly Moss Killers

Iron Sulphate (or Ferrous Sulphate) is the traditional moss control product of greenkeepers. It’s the moss killing component of most killer products and lawn sand.

Pro-Kleen iron sulphate killer is excellent!

It comes as a powder or very fine granules that you mix with water. dissolves well for easy application through a watering can or knapsack sprayer. a

You’ll see the moss turn black within a few hours of applying it and in 7-10 days it’ll have fully killed moss.

This does depend on how thick the moss is though. If your lawn is really thick with moss, it’s often better to rake out as much as you can and apply this ferrous sulphate to kill whatever is left before raking again.

When applied in smaller doses, Iron Sulphate can also be used as a liquid fertiliser to give the grass a boost of green colour, and also harden the turf against the stresses of winter.

You can also use it to suppress the growth of moss over the winter and prevent overtaking your lawn. This makes dealing with it in spring much easier.

Just make sure the grass is wet before applying it. Otherwise, it won’t be as effective.

Overall, this is a brilliant product which I always keep in my shed.

Like I said earlier in this article, there aren’t many granular moss killers on the market. The only one I could find for home use is Evergreen’s Mosskil.

As it’s a granular product there’s no need to dissolve it in water. You can either spread very easily it by hand or with a spreader.

Granular moss killers do take longer to kill moss than liquid products so you’ll need to give it a good 10-14 days to penetrate the moss as deeply as possible.

As such, I’d recommend raking your lawn before applying this product and then raking again a couple of weeks after application.

Unlike pure iron sulphate, Evergreen Mosskil contains Nitrogen which causes the grass to grow. This means you should apply it between April and September when the grass is actively growing.

Don’t apply it in winter, the Nitrogen will cause growth surge which can weaken the grass and make it more susceptible to disease and stress.

Overall, Evergreen Moss Kill is a decent product. It’s easy to spread and it does work although I still prefer Iron Sulphate.

If you’re looking for a pet friendly moss killer, then VivaGreen’s Moss Off is the best moss killer for you.

While regular moss killers use high doses of iron to kill moss, Moss Off is a completely natural and chemical-free product.

It contains natural oils and starches that coats moss in an invisible, biodegradable film. This coating stops the moss from drawing in moisture from the surface or air. And because moss doesn’t have roots, it can’t draw moisture from the ground either. As a result, it dies.

When using Moss Off you’ll notice the moss doesn’t turn black as it dies. Instead, it turns brown. This is because there is no chemical process or reaction.

The fact that there are no chemicals in it also means you can use it all year round, whenever you like. You can also use it as often as you want too.

Although you can apply chemical products like Iron Sulphate multiple times a year, you should always leave a gap of several weeks. This is because you can alter the pH of your soil if you use it too often.

Also, high concentrations of iron in chemical products can cause orange or brown staining to paths and driveways. This staining is permanent.

Moss Off does take a while longer to work than a chemical product. The company behind the product, VivaGreen openly admit this.

If you like to work fast this could frustrate you but in my opinion, the benefits far outweigh the extra time it takes to kill moss.

Also, when compared to a product like Iron Sulphate, Moss Off is pretty expensive. That said, if you’re concerned about the health of your kids and pets, the environment and you’d prefer not to risk ruining other areas of your garden by staining them with Iron Sulphate, I’d say it’s well worth the extra cost.