The hosts of vascular epiphytes differ in many ways, not least in leaf phenology. We hypothesized that differences in microclimatic conditions in evergreen vs. deciduous trees would affect epiphytes at various levels, from organ physiology to community structure. Indeed, deciduous tree species hosted less abundant and species-poorer epiphyte assemblages. Physiologically, epiphyte assemblages differed in the proportion of CAM species and individuals, and in SLA and δ13C values. Effects were also detectable at a demographic level, i.e. in growth and survival rates. Although not all studied epiphyte species showed these effects, the data generally support our basic hypothesis.

The effects of changes in leaf morphology and leaf architecture on plant light capture may explain the common occurrence of heteroblastic species in the understorey of Neotropical forests, which does not negate a simultaneous positive effect of heteroblasty on plant water relations.