1. Leaf formation, loss, retention, longevity and biomass on male branches of the evergreen mediterranean shrub Pistacia lentiscus, L. correlated strongly with water‐use efficiency inferred from leaf δ13C across a gradient of precipitation on the island of Mallorca, Spain. 2. The correlations suggest that the leaf phenology is under control of drought‐induced constraints on the carbon balance. 3. In fruiting female branches, the correlations between the inferred water‐use efficiency and number of formed and retained leaves, leaf biomass and leaf longevity were non‐significant. Leaf formation was strongly reduced by fruiting and the females compensated the reduced photosynthetic capacity by retaining older leaves for a longer time than male plants. 4. It is suggested that leaf longevity in females is under strong control of resource allocation to fruit formation which is ‘overlaid’ on the drought‐induced carbon stress, which led to the observed longer leaf longevity in females than in males.