How to get a lime rate
Send a soil sample to a lab, usually through your state's extension service. The report may say how much lime to apply per 1,000 square feet or per acre. NC State says to divide a rate per acre by 43.5 to convert it. Arkansas puts it plainly: before you lime your lawn, have your soil tested. Most labs work out the rate from a buffer test or the soil's acidity, which a garden pH strip cannot tell you.
The bag matters too. A report gives the rate in calcium carbonate, and Ohio State says to divide by the calcium carbonate equivalent on the label. Ground, dolomitic and pelletized limestone run from about 70 to 95. Hydrated and burned lime are stronger, and Colorado State calls them hazardous to both people and turf, so we leave them out.
If you have no report, the estimate uses Colorado State's table by pH and texture. Treat it as a rough guide. It comes from one region, and feeding and liming decisions both go better with a real test. Clemson makes the general point that soils low in clay need less lime for the same change than soils high in clay.
A worked example
Maryland's example is a report calling for 85 pounds. On a lawn, it says to apply the first 50 pounds now and the remaining 35 pounds roughly six months later. These lines come from the same formula the calculator above runs.
1,000 sq ft of lawn at 85 lb per 1,000 sq ft
- 85 × 1000 ÷ 1000 = 85 lb
- First application: 50 lb
- Later on: 35 lb
- 3 bags of 40 lb
Arkansas splits a little differently. Between 50 and 100 pounds, it says half in spring and half in fall. Above 100 pounds, it says 50 pounds in spring and 50 in fall, then test again. Either way the point is the same: no more than 50 pounds at a time. On a larger job, a 5,000 square foot lawn at 50 pounds with a bag rated 90 takes 278 pounds. Sowing afterward? The lawn seed calculator is next.
Lime estimate by pH and texture
This is the only table by texture that we could read, and it is for soils at about 2 percent organic matter. It shows no units in the text we read, and we take them as pounds per 1,000 square feet from its turf note. Its last rows print as 3.4 to 5.0 and 3.5 to 4.0, which look like misprints. We use the first for anything below 5.0 and leave out the second.
| Soil pH now | Sandy | Loamy | Clayey |
|---|---|---|---|
| 5.5 to 6.0 | 20 | 25 | 35 |
| 5.0 to 5.5 | 30 | 40 | 50 |
| Below 5.0 | 40 | 55 | 80 |
Mistakes with lime
- Per acre or per 1,000. The two differ by 43.5 times, so check which your report uses.
- Too much at once. Four universities give the same 50 pound limit on turf.
- Liming plants that like acid. Arkansas says centipedegrass does best at pH 5.0 to 6.0, and NC State aims for 4.5 for blueberries and 5.0 for azaleas.
- Expecting quick results. Arkansas says several months, and Nebraska says one to three years to peak.
- Treating pelletized as a different rate. Ohio State gives it the same 50 pound limit as ground limestone.
Questions
How much lime do I need to raise pH by 1?
No single figure fits, because clay needs more than sand for the same change, as Clemson says. NC State's own example, from pH 5.0 to 6.0 on one soil, works out to about 34.5 pounds per 1,000 square feet. A soil test gives yours.
Do I need a soil test first?
Yes. Arkansas says to have your soil tested before you lime, and Ohio State strongly discourages yearly lime without testing. pH alone does not tell you the amount, and some plants prefer acid soil, so a test may save you the work.
When should I apply lime?
In spring or fall, by Arkansas, and Ohio State prefers the time when rainfall is most abundant. Do not spread it on wilted or frost-covered turf, and water it in. It works slowly, over several months by Arkansas and up to three years for full effect by Nebraska.
How much lime for 5,000 sq ft of lawn?
No more than 250 pounds at one time, at the 50 pound limit per 1,000 square feet. How much in total comes from your soil test. At 40 pounds per 1,000 square feet on a test report, a 5,000 square foot lawn takes 200 pounds.
How much pelletized lime for a lawn?
The same as ground limestone once you allow for the value on the bag. Ohio State lists the same 50 pound limit for each, and says to divide your report's rate by the bag's calcium carbonate equivalent.
How much lime per acre for a lawn?
Multiply a rate per 1,000 square feet by 43.5, the step NC State gives in reverse. The 50 pound limit per 1,000 square feet comes to about 2,175 pounds an acre at one time. Reports may use either unit, so check which yours gives.
When do I need a professional?
When your report asks for more than 100 pounds per 1,000 square feet, or the pH does not move after a retest. Your county extension office can read the report with you. They can also say if the plants you grow need lime at all.
This garden lime figure is a plan to check against a soil test, since pH alone does not show how much a soil will take. Follow the bag's label for its neutralizing value. Too much lime is hard to undo and can harm acid-loving plants such as blueberries and azaleas. Lime also works slowly, over months or longer, so retest before adding more.
Sources and review
- Soil pH, GardenNotes 222, Colorado State University Extension, 2015, reviewed 2024.
- Liming your lawn, FSA6134, University of Arkansas, 2021.
- Lime and the home lawn, HYG-4026, Ohio State University, 2021.
- Understanding your soil test report, University of Maryland Extension, 2026.
- Soil Test Note 19, 452-719, Virginia Tech, 2025.
- Soil acidity and liming, AG-439-51, NC State Extension, 2018, reviewed 2023.
- Changing the pH of your soil, HGIC 1650, Clemson Cooperative Extension, reviewed 2026.
- G945, Fertilizers for vegetables in home gardens, University of Nebraska-Lincoln, 2005.
Checked in November 2026. Spotted a wrong number? Report it and it goes in the corrections log.
How this is calculated
Every figure below is read from the code that produces the answer, so what is written here is what the calculator ran. The constants were last checked against their sources in November 2026.
The arithmetic
Total
Total = Rate × Area ÷ 1,000
- Rate
- Pounds per 1,000 square feet
Worked through: 85 × 1000 ÷ 1000 = 85 lb
Bag value
Rate of product = Rate ÷ Calcium carbonate equivalent
- Calcium carbonate equivalent
- From the bag, as a share of pure calcium carbonate
Worked through: 50 ÷ 0.9 = 55.56
The constants, and where they come from
LIME_RATE_TABLE
Modelled from published dataEstimated lime by existing pH and soil texture
- 5.5-6.0
- sandy 20, loamy 25, clayey 35
- 5.0-5.5
- sandy 30, loamy 40, clayey 50
- below-5.0
- sandy 40, loamy 55, clayey 80
Applies to: A Colorado table, with soils at about 2 percent organic matter. Your region may differ
Source: Soil pH, GardenNotes 222, Colorado State University Extension, published 2024-09, read 2026-11. This source is about 2 years old, and it is the one the figure rests on.
Also from: Changing the pH of your soil, HGIC 1650, Clemson Cooperative Extension, published 2026-05, read 2026-11.
The table states no units as read, so pounds per 1,000 square feet is inferred from its turf note. It prints rows 3.4-5.0 and 3.5-4.0, likely misprints. We use the first for below 5.0 and leave out the second.
HIGH_ORGANIC_MATTER_FACTOR
Published figureMultiplier for soils at 4 to 5 percent organic matter
Applies to: Colorado State's table
Source: Soil pH, GardenNotes 222, Colorado State University Extension, published 2024-09, read 2026-11. This source is about 2 years old, and it is the one the figure rests on.
Colorado State says to increase limestone rates by 20 percent in these soils, since its table assumes about 2 percent organic matter or less.
LAWN_CAP_PER_THOUSAND
Published figureMost lime at one time on a lawn, in pounds per 1,000 square feet
Applies to: Ground, dolomitic and pelletized limestone on turf
Source: Liming your lawn, FSA6134, University of Arkansas, published 2021-06, read 2026-11. This source is about 5 years old, and it is the one the figure rests on.
Also from: Soil pH, GardenNotes 222, Colorado State University Extension, published 2024-09, read 2026-11.
Also from: Lime and the home lawn, HYG-4026, Ohio State University, published 2021-09, read 2026-11.
Also from: Understanding your soil test report, University of Maryland Extension, published 2026-04, read 2026-11.
Four universities give the same limit. Ohio State gives lower limits for hydrated lime and burned lime, which we do not offer since Colorado State calls them hazardous.
WORKED_IN_CAP_PER_THOUSAND
Published figureMost limestone at one time when worked in, in pounds per 1,000 square feet
Applies to: Soil the lime is worked into, by one university
Source: Understanding your soil test report, University of Maryland Extension, published 2026-04, read 2026-11.
Virginia Tech gives a limit per 100 square feet for established plants, 5 pounds at a time, and half worked in deep at planting above 10 pounds.
SQ_FT_PER_RATE_AREA
Published figureThe area that lime rates are given for, in square feet
Applies to: United States lawn and garden rates
Source: Soil acidity and liming, AG-439-51, NC State Extension, published 2023-10, read 2026-11. This source is about 3 years old, and it is the one the figure rests on.
Reports give pounds per 1,000 square feet or per acre. NC State says to divide a rate per acre by 43.5 to get a rate per 1,000 square feet.
What the labels mean
- Modelled from published data:
- derived rather than measured, calibrated against the source named beside it.
- Published figure:
- taken directly from the source named beside it.
If a figure here looks wrong, it may be. Tell us what you found and we will check it against the source and publish a correction if it needs one. How constants are chosen and how often they are reviewed is set out in our methodology.
How to use the garden lime calculator
- 1
Get a soil test
- 2
Enter the area
- 3
Enter the rate from your report
- 4
Say if it goes on a lawn or into the soil
- 5
Split large doses, and retest before adding more
What this calculator assumes
Every estimate here rests on the assumptions below. Where your job differs from one of them, the figure will differ too.
- A soil test rate is in calcium carbonate, and is divided by the bag's value
- The estimate comes from one Colorado table, and its units are inferred
- Doses split at 50 pounds per 1,000 sq ft on a lawn, and 70 worked in
- Hydrated and burned lime are not covered
Pro tips
- Water it in after you spread it
- Do not spread it on wilted or frost-covered turf
- Retest a few months later before adding more