The uses of sulphate of iron in lawn care

For many years sulphate of iron has been widely used in the lawn and turfcare industry.

It's uses are varied and there are many benefits of applying this product to grass, especially now that many previously used chemicals are no longer available for use on lawns.

Sulphate of iron can be used to control moss, discourage earthworms from casting and in certain cases control weeds and disease.

Many fertilisers used in the turf care industry contain sulphate of iron in their analysis because of the reasons previously mentioned. We will take a closer look at each of the benefits that this product has on lawns and turf.

Disease prevention & control on lawns

Disease's such as fusarium patch and take-all patch require the turf surface to be alkaline (high pH) for the fungus to be active. Applying sulphate of iron the grass will help acidify (lower the pH) of the turf surface therefore minimise the damage caused by the disease.

The product can be mixed with water and applied at a rate of 10g/m2 to the lawn when the disease is most active. For more information on these lawn disease's please visit our disease

In the turf industry fungicides are still widely used for the control of turf disease's as they are more effective than sulphate of iron. However the disadvantages of fungicides is that they also kill the beneficial bacteria (which can help to suppress the disease) as well as the pathogenic bacteria which causes the disease.

At some point in the near future fungicides may end up being banned because of their effect on the environment. If this ban goes ahead this will mean sulphate of iron will play a major role in disease control in the turf industry.

Control & kill moss on lawns

The above photo shows a lawn that has been sprayed with sulphate of iron. Note how the moss has gone black and is ready to be scarified out.

Lawn sand will kill moss very quickly usually between 10 - 14 days however the period of control can be short. It can also be used on it's own at a rate of 10g/m2 to control moss in lawns.

Regular applications at the above rate about every 4 - 6 weeks during the winter months will help stop any moss invading your lawn.

It also has the added benefit of burning of certain weeds if used regularly and preventing algae problems.

Wormcast & worm control on lawns

Unfortunately there are no chemicals that are approved for worm control on domestic lawns, they are only available for turf professionals involved in the turf industry.

However as previously mentioned these product may soon be banned so sulphate of iron will also play a major role in worm control in the turf industry.

Because of its acidifying effect on the turf surface sulphate of iron can be quite effective in discouraging worms and reducing the number of worm casts. This is because worms do not like acidifying effect on the surface caused by sulphate of iron.

Applying sulphate of iron every 4 - 6 weeks at a rate of 8g/m2 should help reduce worm activity resulting in fewer worm casts

Mixing sulphate of iron with water for application

The most effective method of applying sulphate of iron it to mix it in hot water and apply it through a sprayer of watering can. However it can be applied in power form with a spreader. The problem with the spreader method of application is it difficult to apply evenly and as it is very powdery.

When mixing it is important to use hot water and stir if necessary to dissolve the product. It is very important that you mix the product thoroughly as it can easily block the sprayer filters and nozzles.

If necessary you can pour the mixed solution through a filter whilst filling the sprayer to stop any lumps getting into the sprayer and causing a blockage.

Try not to spill any of the mixture on concrete paths as it can stain quite badly. Wear old clothes when handling sulphate of iron as it will also stain clothes too, and wash these separately to avoid staining other garments and fabrics.