Gypsum won't raise or lower your pH level. It's not lime and it has no effect on pH. What it does is add calcium and sulfur to the soil. It also can make a big difference in how quickly water moves into the soil. The trick is having some place for the water to go once it gets into the soil profile.
"We believe the basis of building healthy soil is to start with tile drainage first," says Jack Maloney, Brownsburg. He is an avid no-tiller, and has used gypsum as a tool to help get water into the soil quicker for more than 10 years. He also is very adamant about using cover crops to help manage soil health.
"It all starts with tile drainage," he says. "We tile a field first before we try to convert it to our no-till system.
"If you apply gypsum in a poorly drained soil without tile, there is no place for the water to go. The water will infiltrate into the soil off the surface faster, but then if there is no place for it to go, you will wind up with saturated soils that don't function properly."
The goal, instead, is to have tile lines in place so that once you apply gypsum, which helps loosen the soil and allows water to move into it more quickly during a rain event, the water has somewhere to go," he says.
It moves to the tile lines, and soils don't get or stay saturated. If a soil is saturated without oxygen, soil biology will suffer. Part of the goal of those trying to improve soil health is to improve soil biology.
Maloney says that after applying a ton of gypsum every other year for five years, they definitely notice a difference in how well water moves into the soil.
"We can handle a two-inch rain and we won't have ponding," he says. "That can be hard to do on our soils in a normal year."