Fern vigor indices and estimates of percent marketable yield (PMY) were used to determine alternative measures of asparagus (Asparagus officinalis L.) marketable yield. Total yield was highly correlated (0.75 ≤ r ≤ 0.91), and marketable yield was not correlated with fern vigor indices. The products of fern vigor indices and seasonal PMYs were highly predictive of marketable yield (r 20.95). When the products of each daily PMY estimate and fern vigor index for the same season were determined, then averaged over years, <30% of correlations with marketable yield were ≥0.90, and r values varied considerably during the season. The products, averaged for 2 years, of fern vigor index and mean PMY estimated from combinations of three harvest dates during the season, except from the first harvest week, were associated with marketable yield. For the 40 3-day average estimates of PMY examined, 95% of Pearson correlation coefficients were ≥0.90 and all were ≥0.88. Thus, fern vigor index and PMY estimates from three harvest dates may be used to predict temperate zone marketable yield, decreasing labor requirements for yield trials, and facilitating evaluation of many experimental hybrids.