Determining Sweet Corn Harvesting Time Using Growing Degree Days for 3 Planting Dates Based on Soluble Sugar Content (brix) and Ear Size In Fresno.

California is the second biggest producer of sweet corn (Zea mays L.) for fresh market in the United State, representing 13% of the total value of production of the country in 2009. Fresh market is dependent on consumer preferences of ear quality, such as sweetness, ear size and tip filling, which are affected by planting and harvesting time. Four yellow sweet corn hybrids planted in early, mid and late spring were harvested 6 times, approximately at 200, 250, 300, 350, 400 and 450 accumulated heat units after pollination. Soluble sugar (brix), ear length, girth and tip filling were evaluated to determine the best harvesting time window to get the best quality sweet corn with maximum sweetness, tenderness and flavor. For all hybrids we expect to have the higher quality ears between 300 and 350 accumulated heat units, but we noticed differences among the hybrids based on planting dates. In commercial sweet corn production where harvesting is done once by a combination of machine and human labor, it is critical to pick at the optimum time to maximize production and profitability. This study involving Mirai supersweet hybrids provided some interesting findings under hot Central Valley environments. Since the last harvest is to be done in another two weeks, a more detailed analysis of the results from four plantings will be presented and discussed in detail in the final poster.