Hibiscus trionum

Hours flower

The hour flower (Hibiscus trionum, Syn. Ketmia trionum (L.) Scop, trionum annuum Medicus ), also known as One-year Stundeneibisch, Stundenröslein or Yellow Hibiscus, a plant of the genus Hibiscus (Hibiscus ) in the mallow family is ( Malvaceae ). As the only local representative of this genus in Europe, more precisely in Southeastern Europe, hour flower occurs in Germany only impermanent.

Description

The hour as a flower grows, rarely herbaceous biennial plant and as often reaches heights of growth of about 20 to 50 cm, sometimes up to 80 cm. The stem is hairy little bristly. The leaves have a 2-4 cm long petiole. The 3-6 cm leaf blade has two different forms: simple ovate or three-to five-lobed. The thread-like stipules are about 7 mm long.

Each detached, in the leaf axils, flower opens in the main flowering season from June to September only on one day and then only for a few hours ( hence the name). The flower stalk has a length of about 2.5 cm and extended to fruit maturity up to about 4 cm. The hermaphroditic, radial symmetry, five petals have a diameter of up to 8 cm. The minor calyx consists of twelve fused only at the base, about 8 mm filiform lobes. Also remarkable, the inflated calyx is composed of five to half their length intergrown, greenish, 1.5 to 2 cm long sepals. The five mostly white to pale yellow petals have a dark purple - purple - black base. In the subfamily Malvoideae the stamens of the many stamens are fused into a tube surrounding the stamp, the so-called Columna. The top about 3 mm of the stamens are free. The anthers are yellow. There are five pen available.

The capsule fünffächerige fruit has a diameter of about 1 cm. The seeds are black.

Dissemination

The sun- loving flower hours is from the eastern Mediterranean and Asia, but is common in warm climates almost worldwide. It is hardy and in Central Europe mainly as fickle " weed " on root crop fields, vacant lots and spread along roadsides. Propagation is mainly about self- sowing.