In cold climates, aquatic plants employ a variety of strategies to survive winter, usually by either going to seed, or by producing resistant vegetative tissue that can withstand freezing. Although Lemna minor , the common duckweed, reproduces almost exclusively by asexual vegetative propagation and lacks any additional specific overwintering structure, it thrives over a vast geographic distribution including in northern climates. It is often thought that populations are subjected to a seasonal bottleneck with only a small proportion of plants surviving to found the following year's population. In this study we use experimental enclosures to measure re-emergence of L. minor in a forested pond in Quebec, Canada, after four months of ice cover. Frond recruitment as surface re-emergence and relative growth rate were estimated and compared to the pre-winter population. To our surprise, 92% of fronds survived the winter, indicating the virtual absence of any bottleneck. Lemna minor is then essentially perennial, which despite having a life span of just a few weeks in favourable conditions, can easily endure several months under surface ice cover. • Winter survivorship in Lemna minor is > 90% after four months under surface ice. • Spring populations are founded almost entirely by the re-emergence of overwintering fronds. • L. minor does not appear to be subjected to seasonal genetic bottlenecks. [ABSTRACT FROM AUTHOR]