For both producers and consumers, the onset of asparagus signifies the arrival of spring. The prediction of its emergence involves uncertainty, however, models utilizing growing degree days (GDD) offer guidance. The current season commenced swiftly, positioning the asparagus harvest marginally earlier than the norm.
The recent spring behavior has deviated from typical patterns, with a rapid temperature increase observed from mid-February to mid-March, followed by a cooling period. Unlike other early spring flora, asparagus, with its subterranean crowns, relies more on soil than air temperatures for emergence cues. Michigan State University has dedicated the past five years to track asparagus emergence in commercial settings, employing soil temperature data from the university's Enviroweather system to refine a GDD-based emergence prediction model.
The model indicates that early March's warm soil conditions prompted an earlier awakening of asparagus, though recent weeks have seen minimal progress. Essentially, asparagus's response to the initial warm spell has been to delay further emergence, with future activity hinging on the forthcoming soil temperature trends. Forecasts suggest a return to typical spring warming patterns, with early May projected as a plausible harvest commencement. Updates will be provided by Michigan State University Extension as the season progresses.
Source: canr.msu.edu