Mirabilis jalapa L.

Global description

Mirabilis jalapa is a tall herbaceous plant, reaching 30-70 cm in height, thick branches a little fleshy and swollen nodes, glabrous and regularly branched. The leaves are simple, opposite, ovate to acute apex, rounded or truncated base. The flowers are very delicate yellow or purple trumpet-shaped, long and narrow tube and expanded summit. They bloom at night and fade in the morning and then fall very quickly. The fruits are dry achenes, blach and globose, inserted at the base of the leaves.

Cotyledons

Cotyledons long stalked (2-3 cm), with broader than long blade, almost rectangular of 18-22 mm long and 28-36 mm wide. The base is slightly cordate and the apex slightly truncated. It is trinerved at the base, light green to yellowish green, glabrous.

First leaves

First leaves are simple opposite, borne on a petiole 2 to 3 cm long. The blade is almost triangular in shape, base slightly cordate, 3 to 4 cm long and 2-3 cm wide, rather strongly-veined, light green, glabrous.

General habit

Bushy herbaceous plant because of strong stems branching by 2 or 3.

Underground system

Large tuberous roots.

Stem

Stem solid, square, fleshy, green to reddish, thickened at nodes.

Leaf

Leaves simple, opposite supported by a stalk from 1 to 4 cm long, without stipule. The lamina is fleshy, soft enough, oval, base truncate, rounded or slightly cordate and acute apex from 4 to 12 cm long and 3-8 cm wide. The margin is entire, densely ciliated, hairs multicellular. Both sides are glabrous. The visible nerves are arched.

Inflorescence

Contracted cyme from 1 to several flowers clustered in an involucre of bracts at the ends of branches.

Flower

The calyx, long 7 to 12 mm long is tubular and topped by 5 triangular lobes finely ciliate. The corolla consists of five petals united into a long narrow tube flaring widely at the end. It measures 4-5 cm long and 3-4 cm wide. It is pink, yellow, scarlet, purple or white. The 5-6 stamens of unequal size emerge largely the corolla tube. The style is even longer. The flowers are short-lived, they bloom at night, fade the next morning and the corolla falls off very quickly.

Fruit

Achene, subglobose to ellipsoidal from 6 to 8 mm long, green to black when mature, with 5-10 longitudinal ribs, mute between the ribs.

Origin

Mirabilis jalapa is native to Central America.

Worldwide distribution

This species is widely pantropical, being even naturalized in many temperate regions such as Western Europe, South-East Australia, New Zealand...

https://www.gbif.org/fr/species/3086240