Thanks for your question.

Just so the both of us are on the same page, I have some questions for you:

1). Agricultural lime consists of calcium carbonate. Could you please take a picture of the product label for your agricultural lime and send to us?

2). I am not familiar with “barn lime”. Could you please take a picture of the product label for your barn lime and send to us?

3). What do you mean by “pelletized lime”? Could you please take a picture of the product label for your pelletized lime and send to us?

I need this information for me to provide you accurate answers for your question.

Many thanks.

As a follow-up to my response of 7/23, please be careful in how you are interpreting the lime recommendations on your soil report.  For instance, one report states a need of 3,000 #ENP/acre.  This does NOT MEAN that that you should add 3,000 pounds of any type of lime.  You have to use what is called Effective Neutralizing Power” or ENP.  For me to assist you, I can only do this by looking at the product label for whatever lime you will be using.  Just thinking that 3,000 means pounds may cause great damage to things.

I'm looking forward to obtaining more information from you.  Good luck.

Thanks for getting back to us.  I want to do a bit more research on your situation.  In mean time, read the following.  It may give you an idea of where I'm coming from.  Only recently have soil reports for lime specified ENP.  Previously, it was always in pounds of lime/acre.  I wrote this to inform my fellow Master Gardeners about how to interpret the new reports.

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"Lime is generally used to raise soil pH. Most limes contain calcium carbonate and/or related compounds to cause this elevation. It is generally considered that a soil pH of at least 6.0 is necessary for good garden and lawn growth. Often soil analysis reports would recommend the addition of so many pounds of lime per 100 square feet. Unfortunately such recommendations failed to recognize the types of lime (e.g., hydrated lime, bag lime, garden lime, dolomitic lime, etc.) that are available at garden centers. Moreover the presence of other ingredients in the lime, most notably magnesium salts, affected the ability of the lime to raise pH. Some type of baseline standard was needed. Pure calcium carbonate is now recognized to be this baseline. Consequently the capacity of most commercially available limes to increase soil pH is measured against the effectiveness of pure calcium carbonate and particle size. For example, finely ground lime will be more effective than very coarse lime.

This is the origin of the term “Effective Neutralizing Power” or ENP for short. For example, suppose that 2 pounds of pure calcium carbonate added to100 square feet of garden area caused the soil’s pH to go from 5.9 to 6.0. Call this 100% ENP. If it took just 1 pound of some other form of lime to raise the soil pH from 5.9 to 6.0 in the same 100 square feet, this other form of lime would be twice as effective, pound for pound, as pure calcium carbonate. More specifically it would have (2/1)(100%) or 200% ENP.

Another example: 2 pounds pure calcium carbonate added to 100 square feet of soil raises the pH from 5.9 to 6.0. However, 3 pounds of some other lime is needed to raise soil pH from 5.9 to 6.0 in this same 100 square feet. This other lime is then less effective than pure calcium carbonate. More specifically, it would have (2/3)(100%) or 67% ENP.

In other words, if a lime source is over 100% ENP, it is more effective than pure calcium carbonate, pound for pound, and so less is needed. if a lime source is under 100% ENP, it is less effective than pure calcium carbonate, pound for pound, and so more is needed.

Here's another example from a gardener whose soil report I just reviewed. His soil pH was 5.8. To raise this to pH 6.0, the lime recommendation was 3000 #ENP/A. This meant that 3,000 pounds of ENP was to be added to 1 acre of soil. A widely used source of lime is Horticultural Hydrated Lime made by Hi-Yield. This is often seen in gardening centers.   i'm attaching its product label

It shows an E.N.P. of 130.35%. Here is how to determine how much of this product should be used to satisfy the report’s lime recommendation (keeping in mind that the goal is to raise the soil pH from 5.8 to 6.0):

1. This product of hydrated lime is more effective than pure calcium carbonate. This means that less of it will be needed than pure calcium carbonate.

2. Getting rid of the % marks, I did the following calculation: (1)/(1.30) = 0.77.

3. Then: (0.77)(3,000 pounds ENP) = 2,310 pounds ENP.

4. In other words, to satisfy this recommendation, I indicated that he needed to apply 2,310 pounds of Hi-Yield Hydrated Lime per acre."

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I will get back to you later in the day about your situation.  If in the meanwhile, you have any questions, send them to me.

Thanks again for using our services.

With respect to your question and the information you provided, I can now make some recommendations for which I have reasonably high confidence.

1). I cannot help you if you use Sapp’s lime or the Co-Op product. There is not sufficient information  available to me to arrive at any recommendation.

2). I can make a recommendation about the Fleet Farm product. Specifically I’m talking about the GLC Ultracal product. It comes in a green and white bag. I believe that this is the one which you mentioned. In doing a computer search for its product label, I could not find anything that would help me. However by going to the GLC Minerals website, I was able to access the data sheet for this product. On that sheet was the piece of information I needed. This product has a 100% ENP. This makes life easier for both of us.

Looking at your Field Number 1A recommendation with a #ENP/Acre of 3,000, this is the same as 3,000 pounds of Ultracal/Acre. Since you would be working with 50-pound bag and consistent with the report’s recommendation, an individual bag would cover about 780 square feet. The bag’s directions state that each bag would cover 1,000 square feet. The difference between 780 and 1,000 square feet  may not be all that significant. Whether you use a 50-pound bag per 780 square feet or per 1,000 square feet is your call. I’m smiling about all this, since this is exactly what you were proposing to do before I got involved!! However, I am now confident that this is the correct amount.

In a similar fashion for Field 2, the lime recommendation would be 2,000 pounds of Ultracal/Acre. This would be equivalent to one 50-pound bag per 1,089 square feet. This is essentially identical to the bag specifications that it would cover 1,000 square feet.

What I think is going on is that the coverage amount on the bag is intended to meet a variety of different situations whereas the soil report's recommendations deal with a specific soil sample.

I apologize for prolonging things. However as a Master Gardener, I take pride in answering a question in as accurate a manner as I can. This is what I now feel I have done in your situation. Unfortunately, the exact method of dispersing this large amount of lime is beyond my expertise.

Good luck. Again, thanks for consulting us.