EFFECTS OF NITROGEN RATES AND FINAL FALL HARVEST TIMING ON SAGE (SALVIA OFFICINALIS)

Abstract

Sage is a perennial, semi-evergreen herb and is a multiharvest crop. In a 4-year field study in Bixby, Okla., three N rates, including 60, 120, and 180 kg/h, and four fall harvest dates, including 40 and 20 days before the average first freeze date in Bixby, the average freeze date, and 20 days past the average freeze date were evaluated on sage (Salvia officinalis) production. The fall harvest dates were ≈20 Sept., 10 Oct., 1 Nov., or 20 Nov. each year. Plots were established with transplants in Spring 1990. On all plots, growing-season harvests were executed once in spring and once in summer, followed by the final harvest in the fall annually (1991 to 1994). Results indicated N effects on yield and the N × final fall harvest date interaction were not significant for any of the years. Yields were significantly reduced in the 40 and 20 days prefreeze date harvest treatment plots in 1992, 1993, and 1994 by a hard freeze of –7C on 2 Nov. 1991 with no prior killing frost. Plant stand loss was 61% and 8% in the 40 and 20 days prefreeze harvested plots, respectively. Injury, but not plant loss, in the 20 days prefreeze harvested plots contributed to the yield reduction. Yields in the two later final harvest treatment plots were not affected.