In the current research we focused on adaptations that occur in rye at temperatures just below freezing. These adaptations protect plants from injurious forms of energy caused by dynamics of freezing to lower temperatures. Plants of S. cereale ‘Rosen’ that were subjected to a first (1PH, 3 wks at 2°C) and second phase of hardening (2PH, 4 wks at -3°C) before freeze testing had a greater rate of recovery after freeze testing than those plants that were not hardened (NH) or those that were subjected to 1PH. Elongation of the upper crown and apical meristem during 2PH could, in part, account for the increase in survival. A change from vegetative to reproductive phase could contribute to an increase in carbohydrates. Scanning electron microscopy (SEM) observations, however, indicated that structures in the upper crown did not elongate during 2PH and the meristem of the rye remained in the vegetative state regardless of hardening treatment. Biochemical adaptations during 2PH which might inhibit ice formation or reduce the impact of injurious stresses caused by ice consisted of a decrease in fructan concentrations, and an increase in sugar (sucrose, gluctose and fructose) in both the whole crown tissues as well as in the apoplastic fluid. Sugar increases in the apoplast were above levels attributable to cellular rupture as indicated by the activity of malate dehydrogenase and concentration of glucose-6-phosphate in the apoplast. The changes are discussed in terms of possible mechanisms of freezing resistance.