Using the Soybean Planting Decision Tool to Help Make Planting Date and Maturity Selection

Determining when to plant soybeans and selecting variety maturities are two critical decisions that Iowa farmers make each year. These two decisions greatly affect yield potential and economic return. Typically, soybean variety selection occurs months before soybean planting occurs. An added complexity is current weather conditions at the time of planting.

Through project funding by the Iowa Soybean Association and in partnership with the On-Farm Network an interactive, web-based decision tool was developed to increase the understanding of the complex interactions between maturity selection, planting date and location. The Soybean Planting Decision Tool can be found at;

The Soybean Planting Decision Tool was designed to be a decision-aid for farmers and agronomists. This tool assesses crop staging and frost risks as well as soybean yield response to maturity and planting date. The current version of the Soybean Planting Decision Tool contains a database with more than 107,000 data points that includes APSIM model simulations and field measurements. The tool is designed to allow exploration of 24 planting dates and 12 maturities based on simulated soybean yields using APSIM and a 34-year historical weather record at nine locations across Iowa. The locations used for this web tool development are centrally located within each of Iowa’s nine crop reporting district.

There are a couple of dynamics to be considered with planting date and maturity selection. Generally, there is an ideal planting date window (Figure 1). Planting earlier results in slightly lower yield potential and planting later can result in slight to large decreases in yield potential. This phenomenon dictates that farmers should plant in the ideal planting window or earlier to minimize risk of yield loss due to late planting from excessive rainfall during the planting window.

The Soybean Planting Decision Tool allows farmers and agronomists to identify the interaction of maturity selection and date of planting (Figure 2). It has been long understood and recommended that full season varieties should be planted because of greater yield potential. However, full season varieties require a longer growing season for those higher yield potentials to be realized and earlier planting comes with greater risk of crop failure due to low temperatures and late spring frosts.

The Soybean Planting Decision Tool is currently in version 1.0. The tool is being continuous adjusted as new soybean planting date and maturity trials become available. Additional versions will include greater resolution of the tool to include additional locations, historic weather, and management information. This decision-aid is a unique, multidimensional approach incorporating field research, cropping systems modeling, statistical analysis, and expert knowledge to create a web-based, interactive tool.

Soybean Planting Decision Tool developed as a decision aid to help farmers and agronomists choose soybean maturity and planting dates. The tool can also be used to understand soybean growth and maturity interactions with date of planting.

Source: Mark Licht, Ranae Dietzel, and Sotirios Archontoulis, Iowa State University 

Recent News

Managing Corn Tar Spot in 2020

It’s early in the season, but before we know it, corn will be chest high and we will be thinking about if in season management is needed.  Last year I mentioned that you should “avoid the cosmic freakout” around tar spot.  I again emphasize this statement this season.  Tar spot is endemic to the state […]

Prevent Plant 2020

Some Illinois corn acres are still unplanted due to wet weather. The final plant date for crop insurance has passed for extreme southern Illinois (May 28) and is rapidly approaching for the rest of Illinois (June 5). After the final plant date for corn, farmers who purchased the COMBO crop insurance product can take a […]

Soil Residual Herbicide Options after Corn Emergence

Application of soil residual herbicides is important because they deliver a few weeks of residual weed control and aid in weed resistance management by incorporating additional site(s) of action in herbicide program. Several residual herbicides can be applied after corn emergence without injury to corn. A Few important factors should be considered when addressing weed […]

Your browser is out-of-date!

Update your browser to view this website correctly. Update my browser now