Abstract: To investigate the flowering characteristics and key influencing factors of late-flowering varieties of Handroanthus impetiginosus, we conducted continuous phenological observations over three years (2023~2025) on cultivated specimens in Jinshan Park, Fuzhou City. Correlation analysis was conducted on the observation indicators to explore the effect of meteorological factors on the flowering phenology of late-flowering varieties of Handroanthus impetiginosus. The results showed that:(1) The flowering period of this variety was concentrated in March to April. From 2023 to 2025, the single-plant flowering duration was predominantly 10~19 d. The proportion of flowering plants increased annually but remained below 50%, and the number of plants with concurrent leaf and flower emergence showed a declining trend. (2) Light showed a highly significant negative correlation with leaf fall phenophase, initial flowering and full flowering, while exhibiting a highly significant positive correlation with flowering duration and flower quantity. Leaf fall phenophase showed a highly significant positive correlation with initial flowering and full flowering but a highly significant negative correlation with flowering duration. (3) The initial flowering time of the population and the average initial flowering duration of individual plants displayed an opposite trend to the changes in the mean temperature in February. Specifically, a higher mean temperature in February correlated with an earlier initial flowering time for the population and a shorter average initial flowering duration for individual plants. (4) Light was identified as a key environmental factor limiting its flowering performance. Taking the vernal equinox as the observation node, when direct light duration was below 4 h (shade group), plants failed to flower normally. The flowering rate of the full-sun group was higher than that of the partial-sun group. Additionally, the initial and full flowering times of the full-sun group were significantly earlier than those of the partial-sun group, and both flowering duration and flower quantity were significantly higher in the full-sun group than in the partial-sun group. (5) Plant size showed a significant negative correlation with both initial and full flowering times, a highly significant positive correlation with flowering duration, and a significant positive correlation with flower quantity.