What are you planning to grow in this area?
What is the humus level, organic matter, in this soil?
Who did this soil test and why do they recommend adding any Sulfur to a soil that has barely adequate pH for growing most every plant except those that need a low soil pH such as the Rododendron family?

Quick answers:

Calcium could very well be coming from the shells, but the previous gardener probably limed the site.

The sulfur application is because they didn't test for it, but since it leaches, you most likely need some.

You can use potassium sulfate which is very similar to potassium magnesium sulfate but without the magnesium. Greensand is more of a slow acting long term amendment.

There is no N recommendation for N because they didn't test for it. It is best to assume that you do not have much unless you have been adding manure or compost or had a legume cover crop. Add N at the rate required for the crop you are growing.

"What are you planning to grow in this area? "

Initially broccoli, Brussels sprouts, cabbage, collards, lettuce, spinach, carrots, beets, onions, potatoes, tomatoes, rutabagas and cauliflower all to be planted from August to December at the appropriate times for my area.

"What is the humus level, organic matter, in this soil?"

Soil group--clays and soils high in organic matter (CEC>9.0 cmol kg)

This was tested as bare soil. I have yet to add any organic matter to it. I wanted to fully understand the test results before I added anything. Also, they caution that adding further organic matter may/can raise the P in the soil. Now, having said that, I still plan on adding leaf mold and compost to these beds to improve the texture.

"Who did this soil test and why do they recommend adding any Sulfur to a soil that has barely adequate pH for growing most every plant except those that need a low soil pH such as the Rododendron family?"

This test was done by Auburn university and if I knew the answer to the rest of your question, I guess I wouldn't have to ask. (smile) Why wouldn't they recommend the addition of agricultural limestone if the pH is "barely adequate"?

Fertilizersalesman, thank you for your information. A couple more questions, if I may? Would lime have such a lasting effect in the soil? I'm sure it was limed when it was a garden before but that was at least 20 years ago.

Do you know of any adverse effects of very high calcium levels in soil and if so, are there any ways to counteract tham?

I appreciate y'alls input.

Did you post all the information that was on the test results?

Was there anything indicating Cation Exchange Capacity (CEC)?, percentage of cation saturation or what you've got in the lesser minerals? NO organic matter? NO nitrogen???

I'm no expert, but that seems like a really odd test result.

Is there a phone number on the test, where you could get some answers?

Did you take your soil sample from just one spot?

I would be tempted to send in another soil sample, with a combined sample of several places as far from the shell source as possible (still within your garden area), and see if there is a difference.

Sue

Adding lime each and every year is unnecessary, unless an inadequate amount or the wrong kind is added, (the people at PBS Victory Garden should take note). If you put down the proper amount, and type of lime, that should correct the soils pH for several years.
I asked who did the test because there is no indication of where in the world you are and that Auburn did that test tells me you are in Alabama. High Calcium in the soil can mean a high soil pH and a high soil pH can keep some nutrients from getting to the plants. Most all plant nutrients are most readily available to plants in the 6.2 to 6.8 soil pH range.
Other than adding more organic matter to your soil (it may raise the soils pH and I have seen my soils pH, normally in the 5.7 range, change in some places to 7.2) because that OM will make your soil more workable, I would do nothing more until a future soil test showed a larger problem.

If your garden had been limed 20 years ago it is very likely that is the reason your pH is sill up where it is. In a natural system rain water is slightly acidic and will very gradually lower pH over time. Water moving through the soil leaches bases out of the system as well. The decay of organic materials is also an acidifying process. If these natural process provide more acids than there are bases in the weathering soil minerals the soil will naturally have a low pH. Alternatively in arid low rainfall areas and in limestone areas the soils will naturally have higher pHÂs. In a less than natural system sulfur in the air forms acid rain and will lower pH faster. Adding synthetic fertilizers will drastically and rapidly lower the soil pH. The reason you see farmers adding lime every 3 years is because they are adding a lot of fertilizer every year. Note that not all synthetic fertilizers are acidifying, but the ones that are not tend to be a lot more expensive.

Having a lot of calcium in the soil is not a problem except that it means you are short on another base, in your case potassium. If your soil was high in calcium, magnesium, and potassium your pH would be higher. pH is a measure of the total bassicity/acidity of your soil. The Âpercent base saturation is a breakdown of how the bases (calcium, magnesium, potassium, sodium) are distributed. Ideally calcium takes up 65-75%, magnesium 10-15%, and potassium 2-5%. Sodium is not necessary and is toxic at relatively low levels. Exactly how much that is in lbs per acre or parts per million depends on how much your soil can hold which is represented by the cation exchange capacity (CEC). More clay, and more active (sticky) clay means more holding power and a higher CEC. That is why it takes more lime (base) to raise the pH of a heavy soil than a low CEC sandy soil. Simple eh?

"Simple eh?"

Lol, not as simple as I might have hoped but I think I understand what you're saying. :)

Thank you fertilizersalesman and kimmsr. I appreciate y'all taking the time to respond and share your knowledge with me.

Sherry