Potassium Salts Of Fatty Acids Moss Control Guide
or garden owners, moss is one of their greatest nightmares. These branched, threadlike green plants love to infest shady and damp areas as they form a tangled, thick mat over the soil. Mosses don’t just show up randomly; moss growth is usually a telltale sign that your lawn is facing a more significant issue, such as its growing conditions.
If you notice that mosses are slowly growing on your lawn, here’s a moss control guide to efficiently get rid of them.

Different Causes of Moss
Before we tackle the ways you can do and products you can use to prevent moss growth, here are some of the most common reasons why they grow on your grass or lawn:
Improper Mowing
If you’re the type who mows the grass too short, then it could be one reason for the moss growth. When you cut the grass very short or scalp it, your grass won’t survive because it cannot produce enough food through photosynthesis. It will most likely cause the moss to appear and fill the patches. (Learn How To Get Rid Of Briars)
Highly acidic or alkaline soil
Acidic soils or too much alkaline cause nutrients to lock up and not reach the grass. Once they lack nutrients, the grass blades die and promote moss growth.
Compact soil
Compacted soils can also cause moss. When the soil is very dense, the grass struggles to establish roots and, therefore, won’t be able to receive the nutrients it needs. And you already know what happens – fewer nutrients, more moss!
Tree roots
Yes, tree roots can also be a factor in moss growth. When your lawn is watered deeply enough because of poor drainage, tree roots move toward the soil surface for water and space. They compete with grass, which makes them weaker and allows moss to grow.
Shady areas
As mentioned, grass needs sunlight to produce food so it can survive. Unless it’s shade-tolerant grass, such as St. Augustine or Zoysia, your lawn needs enough sunlight to thrive. When your yard lacks the sunlight it needs because of too much shade, it won’t produce enough food, eventually becoming unhealthy and growing moss.
What Kills Moss?
Wind-blown spores usually spread moss from crusts on the soil surface. Once they’ve spread, your whole lawn is already at risk.
The best way to kill moss is to use moss killers that have active ingredients designated for lawn use. Here are some of the products and ingredients you should look for:
Soap salts
When we say soap salts, it’s either potassium or ammonium salts of fatty acids. Soap salts help control moss in the grass, roofs, and structures like decks and sidewalks. It often comes in liquid form and can also be used for cleaning surfaces. So, when you buy soap salts, you hit two birds with one stone!
Two of the most popular products you can use are the Bayer Advanced Moss and Algae Killer and Safer Brand Moss and Algae Killer and Surface Cleaner. These are proven efficient in controlling moss and even algae in lawns. (Learn How To Keep Roses Fresh Overnight)
Iron-based products
Moss killers also come in iron-based forms, which may contain one of the following: ferrous sulfate anhydrous, ferric sulfate, iron sulfate, or ferrous sulfate monohydrate. They are ideal for moss control in lawns but note that they can stain cement surfaces, so use them cautiously.
Apply 4 to 7 oz of ferrous sulfate in 3 to 5 gallons of water per 1,000 square feet. Some iron is available as a standalone product and in combination with fertilizer for moss control.
Hydrated lime
You can use the hydrated lime by adding 2 to 3 lbs. in 3 gallons of water per 1,000 square feet.
Ways to Prevent and Treat Moss
Killing moss is just the first step to getting rid of them. But the thing is, mosses tend to come back, especially if the condition of your lawn remains the same. Here’s what you can do to make sure your yard is in its best shape where moss wouldn’t dare to grow:
Make sure your soil has good fertility and pH
Most turf grasses require 6.0 to 6.5 pH, while centipede prefers about 5.5 and 6.0 pH. Suppose you need to learn how the pH level of the soil in your lawn; it’s best to consult with a turf specialist and get your soil tested. This way, you’re ensured that the soil in your garden is in its best state.
Improve the drainage of your lawn
You already know how moss grows in damp areas, so you must make necessary changes to your drainage. It would be best to contour it, so water drains off the area properly. Better yet, install tile drainage to fix the wet conditions of your lawn.

Do not irrigate frequently
You think irrigation is what your grass needs, but it does more harm than good. Instead of frequently irrigating them, wait for signs of moisture stress before you irrigate. One of the signs it already needs irrigation is a bluish-gray, dull color. Most of the time, healthy grasses only need 1 inch of water each week during active growth.
Cultivate the compacted soil
Some are available for rent or contract in lawn service companies if you need a core aerator. This machine helps remove plugs of soil and helps reduce compaction.
Fix the light penetration and air circulation.
Removing unnecessary trees and shrubs can help increase your garden’s light penetration and air circulation. If removing them isn’t an option, pruning tree limbs and thinning shrubs would suffice as long as it increases your garden’s overall penetration and circulation.
Frequently Asked Questions
If you still have unanswered questions, these pieces of information might help:
Does salt kill moss?
Salt kills moss in most cases, except for Schistidium maritimum moss species. Salt won’t kill them because they thrive in the salty coastal sea air.
What is the best moss killer?
Here are the most recommended moss killers in the market as reviewed by users:
- Moss Out Lawn Granules – effective in preventing moss from spreading into the lawn, patio, and driveway because it has 32% ferrous sulfate monohydrate and 68% calcium carbonate.
- Scotts Turf Builder Moss Control – it efficiently controls moss while helping replenish lawns after the application.
- Lilly Miller Moss Out Spot Treater – like Moss Out Lawn Granules, it also has ferrous sulfate monohydrate that eradicates moss from the lawn. Thanks to its 10% iron component, it also makes the yard more lush green. They work best with flowerbeds!
- Alpha Chemicals’ Ferrous Sulfate Heptahydrate Moss Killer may be a fertilizer, but it also eliminates moss quickly and efficiently. Mix it with warm water, and it will become an inevitable moss killer.
- Bonide MossMax Moss Killer – You will get rid of moss with this potent spray and mold, algae, and mildew. Its main ingredient is potassium soap of fatty acids, which make it a proven herbicide against moss while not destroying your lawn.
Final Thoughts
Products with soap salts are just one of the many ways to control moss in your lawn. While these products kill the mosses, the best way you can still do this is to prevent the root cause and keep your garden in its best condition. This way, you will no longer have to worry about these mosses to keep coming back! (Read Small Round Holes In Yard – What To Do)
