Soil PH is 7.6 per MSU soil test

Asked December 2, 2016, 3:49 PM EST

How do I lower my soil PH to the range that is recommended for most vegetables? Will the recommendations given for using a 24-0-12 or a 12-0-6 fertilizer be sufficient or do I need to use some form of sulfur?

Thank you, in advance, for your help.

Wayne County Michigan

3 Responses

Since you did not supply your soil test code so I could open your test, the information is going to be general.

I am guessing that your soil test was for vegetables. A soil pH of 6.5 would work for a vegetable garden. There should have been a sulfur recommendation with your recommendation.

You probably not going to find a single bag of fertilizer in 24-0-12 or 12-0-06. You will need to buy a nitrogen fertilizer and a potassium fertilizer. No phosphorus is needed. But neither fertilizer will lower your soil pH. You would have to use garden or soil sulfur.

Depending on the percentage of organic matter in the soil, adding more, if needed, can help buffer the soil but it will not drop the number over a full point. That's way to big.

If you want to send me your soil test code, I can be more specific.

There was no sulfur recommendation with the soil sample results. The fertilizer #s were the ones that were given in the soil sample recommendation. The code for the sample is 62B47E.

Your soil test recommendation indicates per 1000 sq. ft.:

Nitrogen (N): 3-4 lb.

Phosphorus (P): 0

Potassium (K): 1.4 lb.

pH: 7.6... want 6.5

O.M.: 8%... 5 % or slightly above is adequate. You've got enough.

Converting that recommendation to products you can purchase:

You have two choices of nitrogen you can use. You can pick either one, NOT both. If you want to lower the soil pH, either use the 21-0-0 or the 46-0-0 with the sulfur amount. If the pH is alright with you, just use the 46-0-0 and no sulfur.

This is for a 1000 square foot area:

N: Choose either one...

7-9 lb. 46-0-0 (urea) for the entire season. Divide into 3 or 4 applications during the growing season, at least six weeks apart.

10 lb. of garden or soil sulfur per 1000 sq. ft.

-or-

14-19 lb. 21-0-0 (ammonium sulfate) for the entire season. Divide into 3 or 4 applications during the growing season, at least six weeks apart. No sulfur is needed because it is already in this fertilizer.

P: none needed.

K: 2 lb. 0-0-60 (muriate of potash).

How to apply: Divide your seasonal amount of N into either 3 or 4 applications. In the spring, a week before planting, use 2 of your applications and till into the soil at least 6 inches deep. At this time, apply the sulfur if you are using the 46-0-0 and the potassium. The remainder of the nitrogen (either 1 or 2 applications left) are applied during the growing season as side dressing. Sprinkle the require amount od N in the aisles, not on the plants or too close to them.

The nitrogen MUST be divided and all the potassium and sulfur are applied once each season prior to planting. Retest in three years and see how things have changed, including your new recommendation.

It will be almost impossible to find a fertilizer that contains nitrogen and potassium in one bag. Buy them as two separate bags.

If you have any questions, please let me know. This is a big pile of info.