<p>Delayed self-pollination has long been recognized as a potential strategy for reproductive assurance in flowering plants. This study describes a corolla “twisting” movement that occurs during floral senescence in <i>Iris laevigata</i>, which brings anthers into contact with the stigma. To assess whether this movement functions as a delayed selfing mechanism, pollen viability and stigma receptivity were assessed, and seven treatments with 30 flowers each were applied. The results showed that this species was protandrous with pollen viability declining from 84.6% at anthesis to 24.7% at late stage, while stigma receptivity increased over time. In pollinator-exclusion treatments, corolla twisting alone led to approximately 10% fruit set via autonomous selfing. Removal of fall petals eliminated fruit production entirely, which indicated that falls were essential for the twisting movement. Compared to open pollination, seeds produced via delayed selfing had significantly lower seed number per fruit and lower individual seed mass. Additionally, rainy weather reduced pollen dispersal by ~ 80% and fruit set by ~ 40% compared to sunny conditions. Although delayed selfing occurred at low frequency and produced lower-quality seeds, it provided limited reproductive assurance when pollinators are scarce, or weather conditions are unfavorable. This study provides the detailed description of a corolla twisting mechanism in <i>I. laevigata</i> and contributes to our understanding of delayed selfing strategies in the genus <i>Iris</i>.</p>