ABSTRACT
Traditionally saffron is irrigated four times during the growing season. However, to achieve high yields sufficient water is required from October until May. Duration of initial, developmental, mid season and late season stages in saffron is 30, 55, 105 and 30 days, respectively and estimated crop coefficient values (Kt) for these successive stages are 0.4, 0.85 and 0.55. Under Korasan climatic conditions of mid October is the best time for the first irrigation. This should be continued with 15 days' intervals for maximum yield. Summer irrigation has positive effects on saffron yield. However, it is not recommended because of the high risk of fungal diseases.
