moss killer safe for pets

What Lawn Moss Killer is Safe for Pets

Here we discuss the various lawn moss killer and ferrous or iron sulphate products that the homeowner can use without killing their pets and wider family.

Let’s start by stating a few very important points:

  • Any product in the bag if eaten in quantity can be harmful so store out of reach of children and pets
  • You know your pet better than anybody else so if it does have some idiosyncrasies that could cause it harm, then think twice before applying moss killer or allowing it on the lawn
  • Ferrous Sulphate is the most widely used moss control product in the world. Because it is not registered as a pesticide technically it can’t be called a moss killer (at least in the UK) even though it kills moss very quickly.
  • Any product containing Iron (ferrous sulphate) will stain for up to 24 hours after application but can continue for a little longer if applied as a dry product or with lawn feed.

The following is primarily for dogs and cats. See ‘Grazing Pets' at the bottom of the page for alternative advice.

Degrees of Safety of Lawn Moss Killer and Ferrous Sulphate

Totally Safe

MossOff is a unique product for killing moss and contains no harmful chemicals. This means that there are no restrictions on its use and no cautions to observe. It is more expensive than ferrous sulphate based moss killers but does have a residual effect which is very beneficial.

MossOff is in our shop here

Very Safe - Plain Ferrous Sulphate

Pretty much all ferrous sulphate moss products by themselves once diluted and applied are non-toxic, so safe. These are purchased as a dry powder or a liquid and are mixed and prepared in exactly the same way with both doing exactly the same job. The main differences being the liquid will cost considerably more and has a limited shelf life; the powder has no end date.

Products that fit into this category are here

Very Safe - Fertiliser with Iron Sulphate

Still very safe if the combination product is just fertiliser and ferrous sulphate. Both are mineral salts and not toxic. We have two products that fit this category: Winter Green for use from October to April and Evergreen Mosskill for use spring onwards.

Products that fit into this category are here

Generally Safe – No Rake Products

These vary between manufacturers but in general they are very high dose potassium products that can breakdown moss in the right conditions. They can be temperamental to use and take a long time to work so make over seeding timescales very long. For these reasons we do not sell these products and cannot fully advise on their safety.

Caution Needed – Moss Killer with Weed Killer

These are usually fine powdery products and often known as weed and feed, after-cut or 4 in 1. The instructions on the pack usually state to keep pets off for 3 days or until watered in due to the pesticide content. Use with a high degree of caution and adherence to the instructions to maximise safety.

Lawnsmith Moss Products do not contain any weed killer.

Grazing Pets

  • Guinea pigs and rabbits
  • Hens, ducks and geese
  • Tortoise

Any pet that forages at soil level or feeds on grass and weeds is best kept off for at least 3 cuts after any moss control application. Leaving an area of untreated lawn is usually the best approach which can then be treated once 3 cuts have been done on the main area.