Calcium Products - Brian Milam
Calcium Product 98G


Brian Milam

Brian Milam

What are the two types of gypsum; which to choose?

When choosing gypsum it has to be a calcium sulfate di-hydrate (CaSO4*2H2O). This form of gypsum is by far the most soluble form available.

Let’s take a second to review the two major forms of gypsum in the marketplace today in lawn care. The first form is what I mentioned above, calcium sulfate di-hydrate (CaSO4*2H20) and the second form is simply calcium sulfate (anhydrite) (CaSO4). You’re probably thinking, ‘what’s the big deal, gypsum is gypsum and after all it’s only a commodity.’ But there actually is a huge difference. One is very fast acting and extremely water-soluble; the other is not. The di-hydrate form is what you need to look for. This type of gypsum is already infused with two extra molecules of water making it easier to break down.  This makes the nutrients available to the plant as soon as it dissolves into solution; with some brands that’s only a matter of minutes. The anhydrite form does not have any water associated with it and therefore is very hard to break down into solution, sometimes taking years to begin working.

Now that we know the two major forms of gypsum on the market today; now you should know how to figure out which type is which. The info can be found on the back of most bags. The following is what you want to see:


Calcium sulfate di-hydrate (CaSO4*2H20)……92%
Derived from naturally mined calcium sulfate di-hydrate.

Don’t let the levels of calcium on labels fool you. The anhydrite forms will contain upwards of 30% calcium, but they are not soluble and do not break down fast enough to be effective. If the calcium is not available to the plant, it doesn’t matter how much calcium or sulfur is in the gypsum.



145 million years in the making

Often I am asked about our source of gypsum and what makes it so special. I thought I would take this opportunity to share a piece of history with you.

SuperCal SO4 is derived from calcium sulfate dihydrate or, for you chemistry fans, CaSO4*2H20. One of the purest gypsum deposits in the world, happens to be found in a very small region of Webster County, IA, near Fort Dodge.

According to Raymond Anderson in his piece, Fort Dodge Gypsum: A Salt from Iowa’s Jurassic Sea, ”this deposit, part of the Jurassic-age Fort Dodge Formation (about 145 million years old), comprises one of the most pure gypsum deposits known on Earth.”

Anderson went on to explain, “The gypsum at Fort Dodge, like most commercial-scale deposits, had its origins in the evaporation of seawater from a restricted shallow basin. Water from the Jurassic-age Sundance Sea passed over a low-lying barrier into the basin, where the mineral salts became concentrated by evaporation in the hot semi-tropical sun. When the brine became sufficiently concentrated, gypsum crystals formed and settled to the floor of the basin.”

Check out Anderson’s article; it provides an interesting look back at one of Iowa’s most valuable natural resources and gives more insight into why our SuperCal SO4 is so pure!


Fun facts about the snow

Now that Winter Storm Draco (yes, the National Weather Service has decided to name winter storms just like hurricanes) has moved out of the midwest and is headed to the northeast, (I’ve got quite a pile of white stuff here in Wisconsin and our marketing gal in Iowa has a foot of snow at her place!) I thought it might be fun to share some wacky facts about snow!

180 billion
molecules of water in the average snowflake.

15 inches
the width of the biggest snowflake ever recorded

430 inches
amount of snow Stampede Pass, WA receives annually

6 sides
how many all snowflakes have

23 feet
circumference of largest snowball ever made

95 feet
most snowfall recorded in one year at one location

76 inches
record amount of snowfall recorded in a 24 hr period, Silver Lake, CO in 1921

…. I found these facts in my son’s “Boy’s Life” magazine. Hope you all found them as cool as I did!


Goats on the course?

Mowing down unwanted vegetation…

I have been in the golf business for nearly 20 years. Most of the time superintendents turn to mechanical means to manicure their rough areas but in some locations superintendents go back to golf’s roots and employ goats.

Yes, you heard me, goats…check out how these two courses are using our four-legged friends to mow down some unwanted vegetation:

Pasatiempo Golf Club (Santa Cruz, Ca)

Hawks Tree Golf Club (Bismarck, ND)


Subscribe to this RSS feed


Maintained by our team of experts, we have a wide array of blog articles from our experts and guests on topics related to soil and crop health, farming and growing tips, and so much more. If it’s not here, ask us!

  1. Categories
  2. Archives