The article presents for the first time the results of watering of shoots and leaves and heat resistance of 10 introduced apple varieties in connection with their seasonal development and productivity in the extreme conditions of Mangystau. It was determined that the watering of shoots and leaves of apple varieties changed during the vegetation period, increasing and decreasing in connection with the weather conditions. The highest watering of leaves was observed mainly in May, by the end of vegetation leaves watering was minimal. Herewith, periodical decrease and increase of watering (pulsation) was observed during the vegetation period. The sharp drop of leaves watering was observed in the majority of varieties in the middle of August, during the period of completion of fruit ripening and lignification of shoots. Heat resistance also changed during the vegetation period, decreasing from May to September. High heat resistance was observed in the varieties Stolovka and Rennet Burkhardta, which are also characterized by the high productivity.