One of the ideas I got out of The Holistic Orchard was applying gypsum to improve drainage in the heavy clay parts of our garden.  As you can see from the first photograph in this post, a day or two of rain in the winter is all it takes to saturate our soil and create puddles here, there, and everywhere.  Gypsum is reputed to increase drainage and boost calcium levels (which many people believe results in healthier, more nutritious plants) without sweetening the soil, so I decided to give it a try.

When amending soil, it's generally a good idea to perform a soil test first, then calculate how much of the amendment you really need.  In many cases, adding too much is worse than adding none at all, so I was leery when one of our readers recommended: "Be very liberal also. It doesn't burn at all. Also you can used it often." 

However, a bit of research proved him right.  One of Clemson University's soil scientists wrote, "There are no easily accessible guidelines regarding the application rate of gypsum in a homeowner situation.   It is sparingly soluble and so it is nearly impossible to over-apply."  I've seen recommendations as high as 2,000 pounds per acre, which is a lot of gypsum.

In the end, I opted to just sprinkle the pellets across wet soil the way I would if seeding a cover crop, so the first fifty-pound bag covered perhaps a quarter of the forest garden.  The feed store has another 450 pounds waiting for us, so we'll be spreading that slowly but surely as our car and golf cart are up to the hauling.  Most websites recommend repeating the application annually for three years, at the end of which, hopefully, our winter puddles will be less problematic.