Want to help your lawn reach its full potential? A healthy lawn starts with healthy soil. Understanding how lime helps lawns and when and how to use it are important steps! Adding lime to your lawn’s soil is a great way to raise soil pH and encourage proper growth.
What is lime for lawns?
Lime is a soil amendment that comes from natural limestone that is finely ground and used to treat the soil in lawns and gardens. Limestone has a high concentration of two important elements: magnesium carbonate and calcium carbonate. Both of which are used to help neutralize acidic soil.
Lime changes the pH to make the nutrients in your soil more readily available. This is important for gardeners, landscapers and homeowners alike who are looking to get their flowers, lawns and plants growing healthily.
Why does a lawn need lime?
Your lawn will need lime when low soil pH (acidic) begins to inhibit the availability of nutrients needed for healthy growth. While soil pH does vary between different grass varieties, most grasses prefer soil pH between 5.8 and 7.2.
If you have a warm season grass (such as Bermudagrass, zoysia, and centipede) the ideal soil pH is slightly acidic (between 5.8 and 7.0), while cool season grasses (like bluegrass or fescue) prefer a slightly higher pH.
When your lawn’s soil pH is within your grass varieties’ preferred range, the nutrients your grass needs most will stay available. When the pH becomes too high or low, nutrients are restricted.
Why does the soil pH change?
Soil pH can change due to a number of reasons, to include regular lawn maintenance. Normal fertilization, irrigation, root growth, and decay of organic materials can all alter soil pH. Rain and irrigation naturally strip calcium and magnesium from the soil as the water passes through. In most cases, changes in soil pH occur very slowly over time.
Signs Your Lawn May Need Lime
While conducting a soil test is the only way to truly know if your lawn’s soil needs to be treated with lime, there are a few signs to look out for, such as:
Increase in lawn weeds, disease, and insects
- A healthy lawn will choke out most weeds. If you notice an increase in the number of weeds in your lawn compared to the past, get your soil tested. Weeds often prefer acidic soil.
- Low pH can also decrease the effectiveness of some herbicides and insecticides.
Poor grass growth
- Withered grass blades, yellow patches, or areas of patchy growth in your lawn could be a sign that your lawn is in need of lime.
Lawn Moss
- The presence of lawn moss indicates the soil pH has become too low for healthy grass growth.
Fertilizer Not Working
- Most fertilizers don’t work when the soil’s pH is too acidic. If the fertilizer you’re using doesn’t appear to be working, it may be a sign you need to apply lime.
How do I know if my lawn needs lime?
Soil Test
It is important to monitor your lawn’s pH levels regularly. This is done by testing your soil periodically. Without a soil test you will be unable to accurately assess your lawn’s needs. Applying too much lime or applying lime when it is not needed can harm your grass instead of help it.
A professional lawn company can test the soil before treating your yard, or you can contact your local extension office. State extension services, such as those at the University of Georgia Cooperative Extension, offer soil testing for a small fee. You send in soil samples, and they will send back results, giving you a clear picture of the minerals and nutrients in your lawn, flowerbeds or vegetable garden.
If there are times when soil tests show the need for correction, retesting every year is recommended until the appropriate balance is restored. In established lawns, once optimal fertility levels are reached, soil testing should be conducted every two to three years.
How do I conduct a soil test?
Gathering soil samples for testing is not difficult, but it may be a bit more involved than you expect. To learn more, read our related article How to Soil Test or for a complete guide, visit extension.uga.edu. Allow up to two weeks for results to be returned after submitting samples.
When should I apply lime to my lawn?
The timing of lime applications is very important. Typically, the best time to apply lime is in fall when the soil is dry. It can take lime several months after being applied to break down and change your soil’s pH. Applying lime in the fall allows plenty of time to transform your acidic soil before the spring growing season.
Working with a professional lawn care company is highly recommended as they will know the best type of lime and how to apply it properly for your specific soil needs.
*Caution: Lime should never be applied to a lawn that is stressed.
How do you apply lawn to your lawn?
Lime for lawn care comes in pellet and powder form, both are effective in stabilizing soil pH. It is important to apply lime by a tiller or a drop spreader to ensure the application is even and no one area gets too much lime.
- Aeration
Check to see if your lawn needs aeration before applying lime to the lawn. Since lime helps grass roots work more efficiently, lime must seep into the soil, rather than stay on the grass surface or thatch. - Water After Application
It is important to immediately rinse any extra lime off the grass blades since lime can cause them to burn.
How much lime should I apply to my lawn?
The amount of lime to be applied to your lawn will be included in your soil test results based on your specific soil type and current pH. Be sure to follow those recommendations carefully, as the amount of lime can vary drastically for different types of soil.
Applying too much lime to your lawn will remove the acidity from the soil, but will also make it too alkaline for your grass to thrive. Too much lime will cause your grass to yellow and limit its ability to properly absorb moisture and nutrients from the soil.
Hiring a professional lawn care company is the best way to ensure the proper amount of lime is applied to your lawn.
Rules for Applying Lime to Lawns
- Do not apply lime unless a soil test indicates limestone is needed.
- Do not apply ground limestone when the weather is windy. Lime that is blown away is wasted.
- Keep limestone away from plants such as azaleas and rhododendrons that thrive in acidic soil.
- Avoid liming your lawn when there is a danger of frost.
- Do not lime your lawn in summer. High heat negatively affects the chemical process and can cause further imbalance of your soil’s pH.
