Moss can become a serious problem for gardeners as autumn arrives, but there is a remarkably simple method to remove it from lawns without using harsh chemicals. After a dry summer, grass is often left in poor condition, creating ideal conditions for moss to spread.
Healthy, robust grass can usually resist moss, but patches weakened by hot weather struggle to stop spores from taking hold. While shop-bought moss killers may seem like the obvious choice, many are too aggressive and add extra stress to the lawn, potentially harming its autumn recovery.
Why Iron Sulphate Works
Lamara McBride from The Lawn Pack has shared a gentler approach: treating the lawn with iron sulphate. She explained: "The most effective moss treatment in UK lawns is Iron Sulphate (Ferrous Sulphate). When applied correctly it treats moss quickly, turns moss black within days [and] makes removal easier."
Iron sulphate is a naturally occurring mineral compound that provides grass with iron, supporting strong growth, while moss is much more vulnerable to its effects. Iron helps grass produce chlorophyll, which is essential for photosynthesis and energy production, and it also gives the lawn its vibrant green colour.
Treating turf with iron sulphate encourages more robust growth and strengthens the grass, helping it resist moss, weeds and other invaders. While it benefits grass, iron sulphate dehydrates moss spores and damages their cellular structure, causing them to die naturally without the need for manual removal.
How to Apply Iron Sulphate
Start by mowing the lawn before applying iron sulphate, as this allows the treatment to reach the moss more effectively without getting tangled in long blades. Then, distribute the iron sulphate evenly using a spreader, following the dosage instructions on the packet. Applying too much in one area could scorch the grass.
Once the moss has turned black or brown, rake it away and dispose of the dead material in the bin. Water the grass thoroughly afterwards, and the lawn should be moss-free with minimal effort.
Moss typically appears when grass is in poor condition or drainage needs improvement. While iron sulphate removes moss, it is advisable to scarify and aerate the turf some time after treatment. This approach addresses the root cause of the moss growth, giving the grass a better chance of becoming dense and strong before the colder months arrive.
