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Water scarcity in arid regions has led to a decline of surface water available for agriculture. One way to augment the irrigation water supply is to run saline groundwater through an inland reverse osmosis (RO) system and utilise RO wastewater to irrigate salt-tolerant plants. The objective of the study was to improve knowledge of candidate halophyte species for cultivation on RO wastewater land application sites by comparing time integrated germination measurements of seeds exposed to saline groundwater and concentrate from RO facilities. The germination of six halophyte species (Atriplex canescens, Hordewn vulgare, Lepidium alyssoides, Distichlis stricta, Panicum virgatum, xTriticosecale) was studied in 22-day germination tests conducted in growth chambers set to 25/15 degrees C day/night temperatures with 12-hour photoperiods. Seeds of each species were placed in filter paper-lined Petri dishes, moistened with one of four saline treatments (EC 0, 0.6, 4.0, and 10.0 dS m(-1)). Germinability, mean germination time, germination index, Timson’s index and Timson’s modified index were calculated. Results showed that germination percentages were similar within a species across salinity treatments, with the exception of L. alyssoides which showed increased germination under high salinity. Except for A. canescens, all species showed germination delays in response to increasing salinity. On the basis of germination, the six species in this study appear suitable for cultivation on RO wastewater land application sites. However, further investigation is needed to determine salt effects on growth during additional life stages.