How Does Sulphur Work on Lawns?

Sulfur does kill grass, but only if you’re not careful. Putting too much sulfur in your grass can lead to discoloration or the loss of your plants. Throughout this guide, we’ll explain how sulfur can harm your grass and how you can apply it properly. 


What Does Sulfur Do For Lawn?

Sulfur’s primary purpose is to reduce the pH levels in the soil. A high pH level will negatively affect the nutrient availability that the grasses need. When you add the sulfur to the soil, the bacteria convert it to sulphuric acid. 


This natural biological process lowers the grass’ pH levels and makes it more acceptable to nutrients. Ideally, you should have the pH level at a 6.5 – 7.0 ratio. That way, your grass can continue to absorb the nutrients without showing signs of deterioration. 


When having a lawn, ticks and fleas are the most common pests that will inhabit it. In addition, they spread diseases such as Lyme disease and Toxoplasma gondii. Fleas tend to bite, making them a severe threat if you have a group of them flying around on your lawn. 


Ticks will bite and feed on humans and pets. They will stay inside the pet’s fur as a way to infect the human’s later. 


Did you know that sulfur is a good tool for bug control? Once applied, the sulfur penetrates the insect’s eggs and prevents them from hatching. Also, sulfur can repel fleas, making it a great tool if you have an insect infestation on your lawn. 


To explain, sulfur kills off the next generation of eggs and prevents the adult insects’ fleas from entering. This two-pronged approach is what makes sulfur so powerful at lawn management and insect removal. 

When Should I Apply Sulfur To My Lawn?

Because an excessive amount of sulfur will kill your grass, you’ll have to get the exact measurements before using it. The best time to apply sulfur is during the spring. The spring is a great time because that’s when your lawn is the most fertile and able to grow. 


We wouldn’t recommend applying sulfur during the winter. That’s because the grass isn’t stable enough to survive in colder climates. In rainy climates, you’ll want to apply sulfur after it rains to ensure that the water doesn’t wash the chemicals away.


Rather than add sulfur to an established lawn, placing it before you apply sod, seeding, or plugs is a safer method because you won’t burn the grass. Conduct a soil test in the early stages of the process to determine how much pH has to be reduced so it can absorb nutrients. Doing regular soil testing will help you decide if you’re on the right track. 

How Do I Apply Sulfur To My Lawn?

The current pH level and the soil texture will determine how much sulfur you’ll need to apply. For instance, if you have sandy soil with a pH level of 7.5, you’ll have to reduce it to 6.5 by adding 10-15 lbs of sulfur for every 1,000 feet. 


On the other hand, if you have clay soil, you’ll need at least 20-25lbs due to its increased thickness. Since an excessive amount of sulfur can damage your grass, you’ll have to spread it evenly over time. You can apply around 5 lbs of elemental sulfur for every 1,000 square feet. 


If you do plan on applying sulfur during the winter, make sure to apply it every 3-4 during this season. Avoid applying sulfur for more than 10 pounds per 10,000 square feet. 


Sulfur vs. Lime For Lawns

The main difference between sulfur and lime lies in its effect on the soil’s pH balance. For example, lime is used to raise a soil’s pH level, while sulfur is used to reduce it. Still, you’ll need both of them to ensure that your soil is at a reasonable level. 


Before applying lime, it’s essential to make sure that you maintain the people who inhabit the lawn (i.e., pets, children, and adults). The only thing they have in common is that they use a similar process of spreading it around the soil. 

Start by testing the soil’s pH level via a soil pH tester. You can find one at your local garden center. Testing the pH levels will determine how many lines you’ll need to add to the soil. 


Make sure your lawn is aerated before applying lime. This will help the lime penetrate through the soil. Because lime helps the grass grow more effectively, it needs to be deeply ingrained in the soil for it to work. The aeration process gives the lime enough time to blend right in the soil. 


Use a rotary spreader to help with applying the lime on your lawn. Don’t apply lime via hand. The lye within the lime will burn your skin if it gets in contact with it. Wear a respiratory mask to get the dust out of your lungs. 


Once you’ve applied the lime on your lawn, you’ll have to water it. Make sure to rinse the excess lime off the grass to prevent it from burning. 

Sulfur For Lawn Fungus

Sulfur is a great way to remove fungus naturally from your lawn. Fungus tends to reside in alkaline soil, which can be countered if you regularly apply sulfur on your lawn. Changing your soil’s acidity takes time, so expect to add sulfur to your lawn once every 2 weeks to achieve the desired result. 


In addition, sulfur granules are effective at killing off lawn fungus. Make sure you get the 90% strength ones to hasten the process. That way, you’ll increase the chances of adding acidity to your soil and prevent the fungus from growing back. 

Signs of Deficiency of Sulfur In Lawns

Usually, crops get sulfur from the SO2 gas that industrial processes release. In the modern-day, the grass isn’t receiving sufficient sulfur from its natural environment. What caused this change?


Regulations and pollution controls were made to ensure that the spread of sulfur gasses weren’t harmful to humans. While this improved the air quality for humans, it led to less sulfur concentration on the plants. 


The increasing scale of agriculture impacts the sulfur availability. More sulfur is removed due to the increase of agricultural production, such as improved irrigation, intense cropping system, and increasing fertilizer use. 


Also, less soil is added to the grass because of sulfur-free fertilizers like diammonium phosphate (DAP), urea, and potassium chloride. As a result, it leads to reducing the use of sulfur-concentrated fertilizers. 


Conduct a Soil Analysis

To determine the quality of your grass, it’s best to do a soil analysis. This will help you determine how much sulfur is needed to apply on your lawn. The most important thing to remember is that the measurement of the soil needs to be accurate, rapid, price, and correlated with a crop response with soil application. 


The most common form of soil analysis involves using a solution of 0.15 CaCl2. If the soil is less than 10ppm of sulfur, you’ll have soil that’s deficient. Usually, monocalcium phosphate is a good extract. 

You’ll have to conduct plant analysis to see if the sulfur is affecting them. Normally, leaves with less than 0.2% of sulfur are considered sulfur deficient. You’ll have to provide the correct level of sulfur application for optimal yield production and growth. 


You’ll notice that if your grass is sulfur deficient, it will show signs of stunted growth, spindly blades, and yellowing. Sulfur is needed to improve a soil’s pH levels. Microorganisms oxidize the sulfur and turn down its alkalinity to make it more acidic. 


If your soil’s pH has too much alkaline, the grassroots are unable to take iron. But, when the sulfur turns the soil to an acidic level, iron is easier to digest through the grassroots.              


Does Sulfur Kill Grass?

Yes , An excessive amount of sulfur can kill your grass. Before you apply sulfur, it’s best to do a soil test. 


Sulfur is an important nutrient to help in making your lawn grow. While lawns use sulfur in lower quantities than nitrogen, phosphorous, and potassium, it’s still essential in helping the grass stay healthy. 




Will Sulfur Powder Kill Grass

If used excessively, the sulfur powder will kill your grass. Sulfur comes in powder and liquid form and has different levels of application. Place the powder sulfur on the grass to get the first layer of an application.


For any extra cracks and crevices, use the liquid sulfur. You can place the liquid sulfur on your plants and remove pests like scabs and black mold. Use a sifter to help with applying the sulfur powder. 


You should be able to see the color of the ground when applying the powder. Doing so will protect your plants from becoming damaged. 

Does Lime Sulfur Kill Grass?

Yes. Like any form of grass-enhancing chemical, too much lime sulfur will damage your grass. Because of this, it’s best to spray a considerable amount of lime sulfur to ensure that it balances the pH levels but does not kill your grass altogether. 

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