1、 Leaf difference

The leaves of Catharanthus roseus are membranous, obovate oblong, 3 to 4 cm long and 1.5 to 2.5 cm wide. The apex of the leaves is round and has a short tip. The base of the leaves is wide wedge or wedge-shaped, and the base will gradually narrow the layer petiole

The leaves of Impatiens are alternate. The leaves are lanceolate, oblanceolate or narrow oval, about 4 to 12 cm long and about 1.5 to 3 cm wide. The base is wedge-shaped and the edge has sharp serrations.  

2、 Flower difference

The flower cymes of Catharanthus roseus are axillary or terminal, with 2 to 3 flowers, 5-parted calyx, high footed disc-shaped corolla, red, lavender, white and so on

The flowers of Impatiens are solitary or 2-3 clustered in leaf axils, without total pedicel. The flowers are white, purple or pink, and the flowers are single or double