Ready, Set, Plant!

New research from universities, on-farm trials, and seed companies is reshaping how growers decide which crop to plant first.

- Adrienne Held

Across the Midwest, quick swings in weather and fewer workable field days are squeezing an already tight spring planting window.

Manni Singh, associate professor of cropping systems agronomy at Michigan State University, noted that over the past two decades, the number of suitable fieldwork days from mid-April to mid-May declined, dropping from roughly 20–25 days to 15–20. More intense storms, rapid warmups followed by cold snaps, and soils that stay saturated longer leave farmers with fewer opportunities to plant.

“These shrinking workable days make early decisions far more critical,” Singh said. “There are years where you might only get two or three good days in mid-April, and you have to be ready to use them.”

With the window tightening, farmers face a deceptively simple question: Plant corn or soybeans first?

For decades, tradition answered that question: Plant corn first. But university research, on-farm trials, and seed industry agronomists shows the old rule doesn’t always hold up.

“It’s no longer as simple as ‘corn first, soybeans second,’” said Mark Licht, Iowa State University Extension cropping systems specialist. “The research just doesn’t support that blanket approach anymore.”

Across institutions and data sources, the consensus is clear: Both crops benefit from early planting. But soybeans often deserve earlier priority, and corn needs more targeted management when planting gets late.

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