Growing Degree Days (GDD) Through April 23

Jarrod O. Miller, Extension Agronomist,

With the warmer mid-April temperatures, there were some fields planted a little earlier than usual (or at least earlier than last year). It takes 120 growing degree-days (GDD) to see corn emergence. Anyone who planted by Sunday, April 14th should already have seen 120 GDD in all three counties, although it took almost nine days to get there.

Below are accumulated GDD for each county, with the dotted line showing expected emergence. There is an obvious inflection point around April 18th that shows a strong warming trend, before temperatures cooled back off. Had the trend remained in place, it would only have taken about a week to hit 120 GDD. The weather outlook in Georgetown over the next week remains conducive for corn germination, while the northern end of the state may see a few nights below 50°F. However, soils are insulated so we can expect soil temperature to remain in the upper 50s to low 60s. With this weather, we can still expect to see germination and emergence within 7-9 days.