Climate change is causing many plants to fl ower earlier in spring, exposing them to novel selection pressures, including -potentially -pollinator shortages. Over 2 years that contrasted in timing of fl owering onset, we studied reproductive strategies, pollen limitation, and selection on fl owering time in Mertensia fusiformis , a self-incompatible, spring-fl owering perennial. Plants opened most of their fl owers early in the fl owering period, especially in 2007, the early year; but

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... favored early-fl owering individuals only in 2008. However, resource allocation to early vs. late seed production was fl exible: In 2008, but not 2007, early fl owers on a plant produced more and heavier seeds. Late fl owers were capable of equal seed production if fertilization of early ovules was prevented, suggesting that late fl owers serve a bet-hedging function. Evidence for pollen limitation was weak, although there was a tendency for early fl owers to be pollen-limited in 2007 and for late fl owers to be pollen-limited in 2008. Poor reproductive success in 2007 was likely attributable less to pollen limitation than to frost damage to fl owers. We suggest that plasticity in fl oral longevity and resource allocation among fl owers will make this species resilient to short-term pollinator defi cits; whether this will help or hinder future adaptation is unclear.