Southern Ag Manganese Sulfate is labeled for palms, trees, shrubs, vegetables, landscapes, and other plants at 1/3 - 2/3 cup per 100 sq. ft broadcast evenly over an established area.
Unfortunately, we do not have the spreader settings for that specific combo, and since the manufacturer does not list that spreader on their bag we are unsure what the exact setting would be. Due to the thousands of granules on the market and just as many different types of spreaders, there isn't a master list that exists. You may want to try calling the manufacturer of your spreader or the chemical itself directly, to see if anyone on their staff has that info. Otherwise, you will want to calibrate your spreader to the product you are using and its application rates. You can see a short video on how to accomplish this below.
How to Calibrate your Spreader
https://www.youtube.com/watch?v=9vXBjeVA3ao&list=PLG-iVFWQzYnkrUznseZ-SDTcWgflq8DDo&index=39
