I just got soil test results back on several fields — some going to soybeans in 2018, some going to corn. Lime is recommended in all but one field. My neighbor says I should spend my money on lime on the fields going to soybeans and not worry about fields going to corn. Is he right?

The Indiana certified crop advisers answering this question are: Betsy Bower, agronomist for Ceres Solutions Cooperative, Terre Haute; Jamie Bultemeier, agronomist and corporate sales manager for A&L Great Lakes Labs, Fort Wayne; and Steve Gauck, sales agronomist with Beck’s, Greensburg.

Bower: If you can, spend money on all fields that need lime. It’s an investment that optimizes the ability for soil residual herbicides, soil biology, soil fertility and other soil processes to work most efficiently for crops. If you only have so many dollars, concentrate on fields that have the lowest soil pH values to correct, no matter the cropping plan for 2018. It’s true that corn can withstand somewhat lower pH than soybeans. I would still correct the lowest pH levels first. Remember that it takes a full two to three years for soil to become fully neutralized following a lime application. The sooner you start, the sooner you will have improved yields.

Bultemeier: Soil pH impacts availability of all nutrients and nearly all biological functions in the soil, and needs to be the foundation of any soil fertility program. Remember, pH is a logarithmic measurement, meaning each pH unit drops the concentration of hydrogen ions tenfold. The longer you wait to adjust soil pH, the costlier it will be to correct. Frequent light applications to maintain soil pH is more cost-effective. If costs need to be cut, focus lime applications on those fields that require the large lime rates, and those fields with the greatest yield potential, regardless of crop rotation.

Gauck: The pH is one of the most important parts of a soil test. It’s the easiest to correct and has the greatest impact on yields. If your pH is low, make it a priority to spread lime on every acre that needs it. If you can’t spread on every field, target fields with the lowest pH. You will see the greatest return in herbicide and fertilizer efficiency. If you have to choose, I recommend spreading before soybeans. There are studies showing a reaction to calcium before soybeans. Also, soybeans are a scavenger, and a proper pH will release more nutrients into the soil for soybeans to take up.

Bower: If any of your fields are long-term no-till, consider taking zero to 2-inch and 2-inch to 8-inch soil samples to check pH at different depths. If the soil pH problem continues into the 2- to 8-inch depth, strongly consider working in lime and planting a cover crop to stabilize the soil after application. Surface applications of lime on no-till soils take a very long time to neutralize the soil at the lower depths. Jump-start the process by working lime in. A cover crop limits soil erosion losses.