Leaf-out and ﬂowering in any given species have evolved to occur in a predetermined sequence, with the inter-stage time interval optimized to maximize plant ﬁtness. Although warming-induced advances of both leaf-out and ﬂowering are well documented, it remains unclear whether shifts in these phenological phases differ in magnitudes and whether changes have occurred in the length of the inter-stage intervals. Here, we present an extensive synthesis of warming effects on ﬂower-leaf time intervals, using long-term (1963–2014) and in situ data consisting of 11,858 leaf-out and ﬂowering records for 183 species across China. We found that the timing of both spring phenological events was generally advanced, indicating a dominant impact of forcing conditions compared with chilling. Stable time intervals between leaf-out and ﬂowering prevailed for most of the time series despite increasing temperatures; however, some of the investigated cases featured signiﬁcant changes in the time intervals. The latter could be explained by differences in the temperature sensitivity (ST) between leaf and ﬂower phenology. Greater ST for ﬂowering than for leaf-out caused ﬂowering times to advance faster than leaf emergence. This shortened the inter-stage intervals in leaf-ﬁrst species and lengthened them in ﬂower-ﬁrst species. Variation in the time intervals between leaf-out and ﬂowering events may have far-reaching ecological and evolutionary consequences, with implications for species ﬁtness, intra/ inter-species interactions, and ecosystem structure, function, and stability.