# lawn lime difference between brands?



## r7k (Jan 25, 2019)

I need lawn lime, recommendation is 175 lbs per 1000 sq ft to correct low pH.

There is soil doctor dolomite for $6 per 40 lb bag from depot,
There is tractor supply pelletized lime at $4.50 per 40 lb bag,
there is Encap from Ace at $22 per 30 lb bag that says covers 5,000 square feet results guaranteed.

How do I know what to use, or what not to use?
Isn't it all crushed limestone?
How can they say their 30 lbs covers 5,000 sqft? What's so special about their 30 lbs?


----------



## Virginiagal (Apr 24, 2017)

I'm going to copy in a section from Ridgerunner's soil test thread:

"Raising pH in Low pH Soil
Excess soil acidity is neutralize by applying a carbonate source. Lime is used as the source of carbonate for soil pH adjustments. The results from a Buffer pH test are used to determine the total amount of lime needed to raise the soil pH to a desired pH value. (see supra discussion on pH for explanation of the Buffer pH test). 
When a Buffer pH is done by a lab, the soil test report will provide an amount of lime to be applied to raise soil pH (a common target is pH 6.5, but verify with the lab if this is not stated on the report). 
A second note of caution: Some labs make recommendations for only one year of application, so if the amount of lime recommended on the report is for only one year's application, it may not be the total amount of lime needed to raise the soil pH to the desired value. (Once again, if this is not clarified on the report, check with the lab or see the "For the nerds" comments below.) 
A third note of caution, lab recommendation amounts are based on a lime quality CCE number. (If the report does not state the CCE value of their recommendation, verify with them what that CCE number is.) For instance, a soil report might recommend that you apply 100 lbs/M of a 70 CCE lime but the store you go to only carries 80 CCE lime (Bags of lime will always have a CCE value on the bag label) or the report recommends 90lbs/M of a 100 CCE lime but the store only carries 75 CCE. How do you know how much 80 or 75 CCE lime to buy and apply? To convert test CCE amounts of lime to another equivalent amount of lime of another CCE value: divide the test report CCE value by the lime bag being purchased CCE value. Then multiply the test report recommended lime quantity by the result.

"For example: report recommends 100 lbs/M of a 70 CCE lime and the store carries 80 CCE lime.
70 divided by 80 = 0.875. Then 100lbs X 0.875 = 87.5 lbs/M. You need to buy and apply 87.5 lbs/M of 80 CCE lime to get the same acid neutralizing effect as 100 lbs/M of a 70 CCE lime.
For example: report recommends 90 lbs/M of a 100 CCE lime and the store carries 75 CCE lime.
100 divided by 75 = 1.33. Then 1.33 X 90 = 119.9 lbs/M of the 75 CCE. That is the equivalent of 90 lbs/M of a 100 CCE lime.

"Lime is used to adjust pH, NOT Ca and/or Mg levels. Calcitic lime will necessarily raise Ca levels and dolomitic lime will raise Ca and Mg soil levels, but the sole purpose of lime is to adjust pH. The addition of Ca and or Mg is an unavoidable side effect of lime and not the goal. Fortunately, many low pH soils need an increase of Ca or both Ca and Mg. Select calcitic or dolomitic lime based on the soil Ca and Mg levels but only secondarily to pH adjustment. After desired pH is attained, stop using lime and apply gypsum or Epsom Salts to make up any Ca or Mg shortage.
Bag directions for lime application rates should always be followed, otherwise, for Aglime (non-fast acting lime), do not apply more than 100 lbs/M total per year and never more than 50 lbs/M at one time, once in the Fall and once in the Spring (or 25lbs/M every three months, etc)"

Besides the CCE value, you can also compare limes on how finely they are ground (the particle sizes). The more finely ground limes will react quicker. There are powdered limes and pelletized limes, the pelletized ones being much easier to spread. Here is more reading material for you (my article on pH and lime):
https://thelawnforum.com/viewtopic.php?t=1610

Dolomitic and calcitic limes are made from different substances and one may be more appropriate based on your soil test. Dolomitic is probably less expensive.

The fast acting limes like Encap are very finely ground and react quickly, You cannot use 50 lb/1000 sq ft like you can with regular lime but are limited to whatever the bag directs (probably somewhere 10-12 lb/1000 sq ft). You will get a quicker pH change but it doesn't last long term because there is still more reserve acidity in the soil to contend with. So if you need a quick change, it may be worth using a fast acting lime first, then going to the slower but longer acting limes for subsequent applications In your situation, I think the 50 lb/1000 sq ft of regular lime per application is more practical. There should be enough finely ground lime to start working quickly while the larger particles will take longer.


----------

