Submitted to: HortScience
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/6/2023
Publication Date: 3/1/2023
Citation: Williams II, M.M., Dhaliwal, D., Hausman, N.E. 2023. No evidence sowing date influences optimum plant density of sweet corn grown in the Midwestern United States. HortScience. 58(3):301-306. https://doi.org/10.21273/HORTSCI16933-22.
Interpretive Summary: Each summer, sweet corn is sown across a wide range of dates to provide a steady supply of perishable ears for fresh market or processing. The sweet corn industry believes crop density should be decreased in later-sown fields; however, evidence to support this practice is lacking. In field experiments in Illinois, we found no evidence that sowing date influences optimum crop density. Factors other than sowing date likely account for variation in optimum crop density, such as the environment (e.g. weather, soil type) and crop management (e.g. fertility, crop rotation).
Technical Abstract: Sweet corn [Zea mays L.var. rugosa (or saccharata)] is sown across a wide range of dates to provide a steady supply of marketable ears for fresh market and processing. There is a perception in the sweet corn industry that plant density tolerance declines in late-season plantings in the Midwest U.S.; however, publicly available data to support this perception cannot be found. Using field experiments, the objectives of this research were to: 1) quantify the effect of sowing date on growth responses to plant density, and 2) determine the extent to which sowing date influences optimum plant density and maximum yield/profit. There were few main effects or interactions of sowing date on crop growth. More importantly, there was no effect of sowing date on economically optimum plant density or plant density that optimized yield. While variation exists in sweet corn optimum plant densities in the Midwest U.S., that variation is likely driven by several factors other than sowing date which have not yet been identified in detail.