Heat Units (HU) accumulation and predicted vs. observed optimum maturity in Suffolk, VA

September began and farmers may start planning for harvest. With peanut this is not an easy task. Days from planting and HU accumulation are usually used to determine a general harvest time; but fine tuning optimum maturity for individual cultivars, planting dates, and fields is absolutely necessary to minimize yield loss that may result from either rushed or delayed digging.  The table below shows the predicted digging dates based on HU from planting through end of August for Suffolk, VA, and comments on their suitability for estimating actual maturity (Digging Peanut in Virginia-Bailey) (Peanut maturity in VA), which was determined through pod blasting on Sep 2nd.

Based on observed maturity at this time, using solely HU accumulation may result in rushed digging this year.

Planting date HU accumulated through Aug. 31 Predicted days remaining Predicted date Predicted vs. observed maturity
15-May 2324 12 12-Sep Observed maturation through pod blasting shows later maturation than predicted by at least a week for all planting dates
25-May 2271 14 14-Sep
5-June 2058 24 24-Sep

Estimates are based on 2590 GDD required for Bailey to reach optimum maturity and a 22 daily average GDD from Sep 1 through Sep 24.

We will continue to update farmers on peanut maturity in SE Virginia, and encourage Extension Agents to organize pod blasting clinics by mid-Sep in every county.