Artemisia dracunculus L. (tarragon) is a perennial herb in the Asteraceae family, which has a long history of use in culinary traditions. The field experiments was conducted to study the influence of foliar Ca(NO3)2 and KNO3 application on vegetative growth, essential oil yield, content and leaf N, P, K and Ca of tarragon in two harvests. The treatments were performed at four level of foliar Ca(NO3)2 and KNO3 fertilizers (including control (water spray), 2.5, 5 and 10 g l-1) which was set up in a factorial experiment based on Randomized Completely Block Design with three replications. Results showed that foliar Ca(NO3)2 application rates significantly increased plant height, plant width, fresh matter yield, dry matter yield, essential oil content and yield, leaf N, P, K and Ca by an average of 36.2, 41.2, 68.3, 68.6, 23, 88.9,7.5, 16.7, 7.2 and 20%, respectively in first harvest and 50.5, 12.1, 42.7, 65.2, 26.3, 91.8, 11.6, 20.8, 10.2 and 26.9%, respectively in second harvest compared with the control. Also, with increasing the foliar KNO3 rates plant height, plant width, fresh matter yield, dry matter yield, essential oil content and yield, leaf N, P, K and Ca significantly increased by an average of 12.4, 27.6, 121.5, 42.3, 12.4, 75.2, 11.5, 16.7, 9.8 and 21.8%, respectively in first harvest and 26.2, 6.1, 37.8, 49.8, 27, 98.8, 4.2, 16, 42.5 and 6.9%, respectively in second harvest compared with the control. Fresh matter yield, essential oil content, leaf N, P, K and Ca in first harvest and plant height, essential oil yield, leaf N, P, K and Ca in second harvest significantly responded to Ca(NO3)2 and KNO3 interaction. It is evident from the results that Ca(NO3)2 and KNO3 foliar application improved productivity traits, essential oil yield and content and nutrient uptake of tarragon plants.

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