What does a good margarita and a healthy lawn have in common? Lime. Albeit different from the culinary type, lawn lime adds a little “flavor” and balance to turfgrasses by raising their pH levels. So, how can you tell if your lawn needs lime?
A few clues: Your grass may be yellowing, it’s not responding to fertilizer, or your soil test reveals a low pH. Lime helps grass stay green, grow properly, and withstand disease, pests, drought, and weeds. For even more signs your lawn needs lime, keep reading.
1. Your Grass Is Yellow
When soil pH gets too acidic, it can affect the health of your grass — including its color. Expert advice varies, but in general, grass needs a pH level between 6.0 and 7.0 to thrive, with some types preferring soil that’s slightly more acidic (e.g., tall fescue) and some preferring soil that’s slightly more alkaline (e.g., St. Augustine grass).
2. Weeds and Moss Are Prevalent
Acidic soil doesn’t only affect grass color but also other indicators of health like grass thickness, disease/pest occurrence, and nutrient absorption. And when nutrients aren’t readily available, turfgrass can start to die off; this leaves things wide open for weeds and mosses to swoop in, take over what nutrients are around, and cover any bare spots.
3. Fertilizer Doesn’t Help Your Grass Grow
For most homeowners, fertilizer is the go-to when they notice their grass isn’t growing properly. But, if you discover your lawn is still lacking even after you’ve applied a treatment, it could be a sign that you actually need lime, instead.
Why? Adding fertilizer to soil that’s too acidic won’t magically allow nutrients to penetrate your grass’s roots. You have to increase the soil pH first to make that happen. In fact, adding fertilizer in such conditions can cause even more damage; it may lead to an overabundance of nitrogen, which can further throw off your soil’s pH.
4. There’s Been a Lot of Rain or a Season of Drought
A muddy yard isn’t the only thing you could be dealing with after a deluge of rain; too much water can affect your soil pH, too. This is because excess water can strip your soil of essential nutrients like potassium, calcium and magnesium, washing it away with the rest of the runoff.
Lime adds those nutrients back into the soil, not only replenishing it after stormy weather but also enabling it to withstand times of excess heat and drought. If your soil lacks these nutrients, it won’t be able to take in water well due to stunted root growth and won’t just go dormant for a bit; it will die off. Don’t know the difference? Check out our article Dormant Grass vs. Dead Grass.
5. You’ve Got Sandy or Clay Soil
Since these soil types are naturally acidic, you’re going to need to add lime to increase the pH and make it more hospitable for the lawn growth you’re after. Sandy soil, specifically, has a hard time retaining water, and both types have difficulty holding on to essential nutrients; adding lime can help improve the retention of both. Amending clay soil with lime also makes it looser/easier to break up, so you won’t expend so much energy pulverizing soil that feels more like plaster when it comes time to plant grass seeds or plugs.
6. A Soil Test Reveals a Low pH
Of course, the most accurate way to determine if your soil needs lime is to conduct a soil test. These tests should be done about every three years, and they measure everything from pH to soil texture to nutrients. The results help you decide what, if any, amendments you need to incorporate into your soil.
You may be able to get this done for free by your state extension office; just send your soil sample to their lab for testing. Or, you can purchase a kit at your local hardware store. Note: The tests you get from your extension office will be more accurate.
FAQ About Adding Lime to Your Lawn
Can you put too much lime on your lawn?
Yes — while the right amount of lime can raise your soil pH just enough to make it more hospitable to turfgrasses, adding too much lime can make your soil overly alkaline and cause your lawn to die off. Similarly to soil that is too acidic, soil that is too alkaline won’t be able to properly deliver nutrients and water to all parts of the grass plant.
When should you not apply lime to your lawn?
There are a few situations in which you should avoid liming your lawn:
- When grass is visibly wilted
- When grass has a covering of frost/predicted frost
- During the middle of a drought/period of high heat
- When your soil test shows your lawn’s pH is already balanced
How long does it take lime to work?
Don’t expect an overnight miracle — lime will take some time to work its way through your soil. Just how much time depends on several factors, including the type of lime you use (pellets or powder) and your soil’s pH level and moisture content. Expect to start noticing changes anywhere from several weeks after application to several months.
For best results, be sure to evenly spread your lime and water it immediately after application. Water will not only wash the lime off the surface of your grass blades (helping ensure kids and pets don’t accidentally get skin irritations from rolling around in lime), but it will also help activate the lime to begin penetrating your soil.
Hire a Pro to Maintain Your Lawn
Liming your lawn is a pretty easy DIY task — all you need is a spreader or bucket. You can use your soil test results to calculate the amount of lime you need, and get to work. But, if your energy taps out after that bit of manual labor, leave the rest of your lawn tasks to a professional lawn care pro near you.
Not only can they handle the mowing, trimming, and edging, but they can also advise you on fertilization, watering, weed control, and aerating. Then, you’ll have a healthy lawn that lasts season after season.
Main Photo Credit: Horticulture / Adobe Stock
