Seed banks of terrestrial and aquatic plants allow the survival of populations when faced with adverse conditions. While there is a substantial amount of research on the effect of temperature on seeds of terrestrial plants, there are few studies that have examined the effects of temperature on seeds of aquatic and semi-aquatic plants. Given that floodplain sediment temperatures in south-eastern Australia have been reported as exceeding 40oC and as high as 70oC it could be predicted that seeds should be capable of persisting under these conditions for periods of time. This project investigates the impact of increasing sediment temperature on the germination of seeds of 4 common wetland associated plants. Seeds were collected from four common plants found associated with rivers and wetlands (Alternanthera denticulate, Juncus usitatus; Persicaria lapathifolia; Persicaria prostrata) and exposed to 6 temperatures between 25°C and 100°C for durations between 1 and 14 days. Seeds were then germinated on agar in a constant temperature cabinet. Results indicate that seeds can withstand heating up to 60oC with no loss of viability. However, future climate change scenarios predict an increase in air temperature of up to 4°C by 2070. This prediction has the potential to increase sediment temperatures by up to 10oC. The projected sediment temperatures may exceed the threshold of many aquatic and semi-aquatic plant species. Previous experiments have indicated that seeds of aquatic plants are sensitive to high temperatures with germination ceasing once temperatures exceed 50oC.