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During the course of a year, we studied the water and metabolic status of Asphodelus aestivus, a mauve geophyte of East Mediterranean, dominant in areas degraded by overgrazing and fire. The species proved to be very efficient in storing water during the long summer drought. At soil water content values around zero, in the upper part of the soil profile(10-20 cm in depth), the roots remained hydrate and turgid, their relative water content was >60% and water potential >-1.6 MPa. Accumulation of proline during winter in leaves (ca 5 mg g-1 dry weight) and tubers (though at significantly lower levels, ca 1.5 mg g-1) might be taken as evidence of a winter cold stress response. Proline accumulation in tubers, under summer drought, was similar to that in winter. Maximal values of caloric content were recorded in expanding leaves (ca 5600 cal g-1 dry weight) and minimal before leaf senescence. In contrast, root caloric content remained fairly constant for most or the year (ca 4550 cal g-1 dry weight) in spite of drastic changes in the concentrations of soluble sugars, starch and lipids. Long before senescence, photosynthetic products were translocated to the below round system, where they were stored. Drastic changes of the storage compounds were observed before emergence of the flowering stalk, far greater in magnitude than those before leaf emergence. The below ground part of the species was found to be less susceptible to climatic stress and to constitute an energetically rather stable system. The physiological processes of the species were well synchronised to the fluctuations of the Mediterranean climate. [ABSTRACT FROM AUTHOR]