You've probably heard a lot of old sayings, but you probably haven't heard of this one. You know when it is OK to plant corn in the spring by what asparagus is doing. If the asparagus is poking through the soil, you can start planting corn.

If you want a more technical answer to the "when to plant corn" question, try this. But believe it or not, the asparagus approach is actually more of a true statement than an old saying, as far as Richard Kohlhagen is concerned.

He farms with his wife, Carol, and several family members in Jasper County in northwest Indiana. Many of their soils are on the sandy side.

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Right temperature, right time: When the soil temperature reaches 55 degrees, and the asparagus is coming up, it's time to plant corn- at least that's what some farmers and agronomists say.

Asparagus has always been a part of their operation. While they once raised 40 acres, today they raise about 10 acres of asparagus.

From more than 40 years of experience, Richard is convinced. "On our soils if the asparagus is coming up, then you know you can plant corn," he says. "If the ground is warm enough for the asparagus to begin growing, then it's warm enough to sprout corn and get it out of the ground. I've learned that over the years, and it's about the best sign I know for gauging when to start planting corn."

Exactly when that is varies with the year, he notes. It's highly dependent on spring weather. A few years ago it was very late March. That actually was 2012, the year to forget. Usually in their part of the world it's sometime in April.

Dave Nanda, a consultant with Seed Consultants, Inc., is a firm believer in early planting. However, he also knows the temperature needs to be 55 degrees F to germinate corn.

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Whenever you think the soil temperature is at least 55 and it appears it will stay there and continue to warm up, it's time to plant corn, he believes. How you decide if it's the right temperature is up to you. Use a soil thermometer, or watch the asparagus come up! The choice is yours.