Caution—don't plant on soils that are too wet—even if your soybean planting has been delayed and you are itching to get the crop in the ground. "Remember--soil conditions at planting are important if you want to get a high yield," emphasizes Palle Pedersen, Iowa State University Extension soybean agronomist.
Remembering last year, many Iowa soybean farmers are now wondering whether this spring's rain has already delayed planting enough to hurt yield potential. "However, it is not yet time to worry," says Pedersen. "In Iowa, we're not doing too badly. The rain has been sporadic and farmers have been able to do some fieldwork. Currently, farmers have about two-thirds of the corn planted and a few soybeans--statewide."
Soil condition important for high bean yield
It's important for soil conditions to be right for planting. Pedersen acknowledges that in a normal year, you should try to be finished planting corn by May 10 and finished planting soybeans by May 15--to reach full yield potential in Iowa. However, Pedersen also emphasizes that it doesn't pay to plant when the soil conditions are not suitable.
"If you plant in a wet seedbed, it will often lead to sidewall compaction. That keeps a good root system from developing and that will affect nutrient and water uptake. A fully developed root system is critical, particularly if we get into a hot and dry summer," says Pedersen.
Don't make same mistake again this year
He uses last year as an example. "Last year many farmers were forced to plant soybeans into seedbed conditions that were less than favorable, and we saw a lot of sidewall compaction because of that," says Pedersen. "But fortunately, because there was enough rain throughout the summer and the temperature was cool enough during the growing season, we still got a pretty good crop."
Right now, he says, there is still some time left before the planting situation becomes urgent. Also, rains that have been occurring in Iowa in recent days have been spotty, which means some farmers in the areas that are missed by the "hit and miss" showers have been able to get some fields planted.
"Pay attention to seedbed conditions. That is critical," adds Pedersen. "We are now at the end of the first week of May and we still have more than a week to go yet to plant our soybean crop before we start losing significant yield. And, keep in mind that Iowa farmers have the capacity to put in a million acres in a day. We saw this a few weeks ago--in the third week of April when the weather was good and a lot of corn was planted in a short period of time. It's still too early to worry and compromise on wet seedbed conditions."
"It's early enough that I don't think we in Iowa should worry yet. In other states, including Illinois and Indiana, where they barely have any corn planted, it's a whole other story." For a podcast that provides further more information on this topic and other information on soybean management, go to www.iasoybeans.com/productionresearch.