Spring frost is a significant production hazard in nearly all locations of temperate zone viticulture. The occurrence of spring frosts can sometimes cause considerable yield losses in many vineyards located in cold regions of Iran. Many Iranian vine growers use the ‘Kazandeh’ training system, to protect the trunks and canes from freezing damage by burying with soil or mud in the fall and winter seasons. The purpose of this investigation was to determine the best time for bringing out vines of the ‘Bidan Sefid’ cultivar, from the subsoil or sub mud from the late winter to early spring. The experiment was conducted during 2015-2016 with randomized complete block design (RCBD). The treatments consisted of removing out trunks and canes from the soil four times (March 16, April 4, April 24, and April 30 (as control)). The effects of the remove-out times were measured on some physiological and morphological characteristics. Results showed that vines that were removed from the soil in late March had more damage than other treatments, and there was no significant difference in damages between the vines that had been removed from the soil during the period from April 4 to 24. Furthermore, results indicated that high carbohydrate storage and proline concentration could affect increasing cold tolerance in vines.
