About Impatiens walleriana Hook.fil.
Impatiens walleriana Hook.fil. is a herbaceous perennial flowering plant that reaches 15โ60 cm (6โ24 inches) in height. Its broad leaves are 3โ12 cm long and 2โ5 cm wide; most leaves grow alternately along stems, though they may be arranged oppositely near the top of the plant. These simple, variable leaves are borne on stalks 1.5 to 6 cm long. The leaf blade ranges from ovate to broadly elliptic, and is sometimes obovate, measuring 2.5 to 13 cm long and 2 to 5.5 cm wide. Foliage is green; the underside of leaves is sometimes spotted, or tinted pink or reddish. This species does not produce leaflets. Stems are semi-succulent, and all soft plant parts (leaves, stems, flowers, roots) are easily damaged. It produces large quantities of hermaphroditic, zygomorphic flowers that are 2โ5 cm in diameter, with five petals and a spur. The lower sepals are slightly boat-shaped, and narrow abruptly into a 3 to 4.5 cm long, thread-like, curved spur that is not recurved. Like other species in the Impatiens genus, its ripe seedpod explodes to disperse seeds, an evolutionary adaptation for seed dispersal.
While it grows as a perennial in frost-free climates, it is most commonly treated as a half-hardy annual in temperate regions, though potted plants can be successfully overwintered indoors. It is one of the most popular bedding plants for parks and gardens worldwide, grown both in containers and as part of outdoor bedding displays. It can be propagated by seed or stem cuttings; stem cuttings often root readily when placed in water.