Paeonia broteri is a perennial, herbaceous plant of 30–80 cm in height. It is a diploid species with ten chromosomes (2n=10).
Roots, stems and leaves It has carrot-shaped roots up to 3 cm thick, from which the plant regrows early in spring, when conditions are best for plant growth in its home range. It also has thin lateral roots. Its stems are often tinged purple. Its leaves consist of three sets of mostly three leaflets, which may be deeply incised themselves, resulting in ten to thirty oval or longish oval segments (1½-5 or rarely up to 6½ cm wide), with a wedge-shaped foot, a more or less pointy tip, shiny bright green upper surface, and a (nearly) hairless, distinctly blue-green underside. In its home range, this species has flowers from late March to May, but in The Netherlands flowering occurs in June and early July. The seeds are about 7–8 mm in size, reddish at first but blackish when ripe.
Differences with related species Paeonia broteri is closely related to
Paeonia clusii and shares the same characters except for the different average numbers of leaflet segments: 11–32 in
P. broteri, 23–48 in
P. clusii subsp.
rhodia and 23–96 in
P. clusii subsp.
clusii.
P. broteri also looks like the
sympatric P. coriacea, but this species can be distinguished by its hairless carpels and wider leaflet segments (2–8 cm).
P. mascula may also be confused with
P. broteri, but this has only ten to eighteen (seldom up to twenty one) and larger (4½–18 × 3–9 cm) leaflet segments, while its carpels are mostly hairless and if present the hairs are about 2 mm long, whereas the densely hairy carpels of
P. broteri carry hairs about 3 mm long. The distinctiveness of
P. coriacea and
P. mascula from
P. broteri is confirmed by their
tetraploidy (2n=20), while
P. broteri is a diploid. == Etymology ==