By now, most watermelons have been planted in southern Indiana, and most fields are currently in the vegetative growth stage. The earliest planted fields have begun to set fruit.
In the past two weeks, I have observed herbicide damage in a few watermelon fields. Although the application rate and method were consistent with the labels and have worked well in previous years, heavy rainfalls immediately following herbicide application and transplanting could have splashed the chemicals onto newly planted seedlings, potentially causing damage. Additionally, runoff after heavy rains may have carried higher concentrations of herbicide to lower areas of the fields, resulting in damage.
The frequent rains throughout April and May have made fieldwork particularly challenging this year. In some cases, planting was delayed, causing transplants to become stressed as they remained in small-cell trays for an extended period. These stressed transplants, combined with high temperatures shortly after transplanting, have led to transplant establishment failures or stunted growth in some fields.
Farmers are now starting fungicide applications. Some are curious about the status of MELCAST. The MELCAST site (melcast.info) is operational. Watermelon and cantaloupe growers can find the updated EFI values by selecting a nearby location. For those new to MELCAST, the publication “Foliar Disease Control Using MELCAST” provides guidance on using this tool. For specific fungicide recommendations, please refer to “Cantaloupe and Watermelon Fungicide Schedule” updated by Dr. Dan Egel in December 2023, and mwveguide.org. As many of you are aware, Dr. Dan Egel retired earlier this year. As a result, there will not be a hard copy of MELCAST newsletter this year. However, the exciting news is that we are expecting a new plant pathologist to join us in July. In the meantime, I am happy to answer questions if I can.