Abstract: Using 85 ornamental peony cultivars as materials, flowering phenology observation and analysis were conducted. The results showed that based on the initial flowering date, the 85 cultivars could be classified into three sequential groups: Early-flowering group (E), medium-flowering group (M), and late-flowering group (L), with a time span of 16 days for the initial flowering date across the groups. Based on flowering duration, using a 4-day difference as the class interval, the cultivars could be categorized into three duration types: Short-flowering (S), medium-flowering (M), and long-flowering (L). The average flowering duration of the 85 cultivars was (8.7±2.5) days. Dynamic function models for the Cultivar Frequency Index (CFI) were constructed for three stages: Initial flowering stage (S1), full flowering stage (S2), and final flowering stage (S3). Through analysis of the cultivar display index (CDI), the optimal viewing period for the peony population in Luoyang was determined to be from April 8 to 14. Correlation analysis between flowering traits and meteorological factors indicated that daily mean temperature was significantly correlated with initial flowering date (r = 0.633), full flowering date (r = 0.725), and final flowering date (r = 0.405).

Key words: ornamental peony(Paeonia suffruticosa Andr.), flowering period, phenological sequence, meteorological factors, correlation analysis