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The role of dew, fog, and rain in the development of reproductive organs in the moss Bryum dunense A.J.E. Smith & H. Whitehouse (B. bicolor complex) was examined in three different microhabitats within a dune field in the Negev Desert. Growth and reproduction were compared prior to the first rainfall of the winter and subsequently, twice during the winter. The microhabitats, differing in their exposure to radiation and precipitation, were 1) an exposed site, 2) a shaded (under a shrub canopy) site, and 3) a partially shaded microhabitat at the foot of a north-facing dune slope. We hypothesized that both microhabitat and time of year would impact the reproductive strategies of the species. In all three microhabitats, reproductive organs were initiated prior to the first winter rain. The source of bryophyte wetness was atmospheric humidity front dew and fog. The type and the extent of development of the reproductive organs was habitat dependent. Prior to the rains, antheridia and archegonia were scarce in the exposed microhabitat, in small numbers in the shaded microhabitat, and most abundant in the partially shaded microhabitat. Subsequently, sporophytes were formed more often in the partially shaded microhabitat following the winter rains. Asexual propagation by bulbils was prevalent at the partially shaded and the exposed microhabitats, whereas regeneration by secondary protonemata was especially abundant at the shaded microhabitat. Bryum dunense is highly adapted to dew and fog utilization and is able to develop reproductive organs prior to the first rains. In this way, plants arc, prepared for dispersal by bulbils and ready for fertilization. with the onset of the first rain. This earl.), initiation of reproductive development is especially advantageous for dioicous species in unpredictable desert environments enabling the completion of the life cycle. The partially shaded microhabitat formed by the shrub canopy was found to be the most suitable microhabitat, yielding the highest amounts of sexual (antheridia and archegonia) and asexual (bulbils) organs. The shrub may thus serve as an ’island of fertility’ for B. dunense.