Paeonia broteri

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.[5]

Paeonia seeds

The flowers are set individually at the top of the stems, are mostly subtended by one or two bracts looking like a leaf segment, and may be up to 15–16 cm in diameter. It has three, sometimes four, sepals, green with a purple margin, of approximately 3 cm long and 2½ cm wide, with rounded tips. There are five or six magenta or pinkish magenta petals, each 5–6 cm long and 3–4 cm wide. Numerous stamens consist of cream-colored, yellowish or purple filaments topped with yellow anthers. There are mostly two or three (occasionally one or four, rarely five) carpels covered in 2 mm long rust-colored hairs, with at their tips very short red stigmas of 2½ mm wide, their base encircled by a 2 mm high disk. The fruit consists of two to three (seldom one or four) follicles, each of which is up to 2½-4 cm high, and is covered in dense felty hairs which persist when fully grown.[5][6] In its home range, this species has flowers from late March to May,[7] but in The Netherlands flowering occurs in June and early July.[8] The seeds are about 7–8 mm in size, reddish at first but blackish when ripe.[3]

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.[5]