And despite winter officially ending weeks ago, the soil temperature is still too low.
“The soil is going to have to be at least 50 degrees for corn to germinate,” Carlton said. “At 50, it could take three weeks to grow, so really, we need soil temperatures above 60 or 65 for optimal germination. Thursday in Wapello County it was 54 degrees. And it dropped to 45.”
A higher soil temp has another benefit, he said. Farmers who have seen their corn suffer the fungal pythium rot will find that the toxin becomes inactive when the soil gets above 65 degrees. Waiting for the topsoil to dry a bit, and for temperatures to go up, is just going to result in higher yield. He acknowledges it can result in a higher anxiety level, too.
“It’s hard to be patient,” he said.
There’s a difference between the perfect time to plant and what a farmer considers practical. There have been times in the past when Carlton advised farmers that the optimum planting time would be in a few days. Then, a farmer waits — and it rains, muddying the field again so they can’t plant.
“My comment would be you’ve got to do what you’ve got to do,” he said. “In general, my advice would be to wait until the planting conditions improve. We’ve got to wait until the soil temperature is well above 50 degrees and rising and the mud in the fields has started to dry.”