Technical Abstract: Potato is one of the most important crops worldwide. Frost damage to the foliage is a common problem where potatoes are grown and results in extensive reductions in tuber yield. In contrast to the commercially cultivated potato (S. tuberosum), some wild potato species possess different levels of cold tolerance and/or acclimation capacity. Previous studies suggest Ca2+ as an important factor in the maintenance of membrane integrity and membrane transport functions. The main objective of the present study was to find out if supplemental calcium fertilization could increase the levels of freezing tolerance in different potato species. For this purpose, the freezing tolerance of a broad spectrum of the Solanum taxa was evaluated with and without supplemental calcium fertilization. Most of the species that were grown in the field with extra calcium supplements showed somewhat greater frost resistance, and this effect was usually more evident among the frost hardy species. Future breeding schemes may be able to use this information for selecting frost tolerant clones or clones that would respond positively to calcium fertilization in terms of frost survival.