Helianthemum nummularium
Yellow Rockrose
Called The Yellow Rockrose ( Helianthemum nummularium ), even ordinary Rockrose, vulgar Rockrose, rock rose and Midsummer herb, a plant belonging to the family of rockrose is ( Cistaceae ).
Features
The perennial, woody at the base plant reaches heights of growth 10 to 30 centimeters. The leaves are elliptic with constant - ovate, entire and ciliate. The lanceolate stipules are longer than the petiole.
The most einseitswendige, racemose inflorescence is wenigblütig. The hermaphrodite, radial symmetry, five petals have a diameter 8-18 mm. The sepals are often reddish - streaked. The five petals are lemon to golden yellow. There are many stamens present. The flowering period extends from May to September. The capsule fruit contains many seeds.
Ecology
The Yellow Sun Rose is a low -lying (up ascending ) shrub with evergreen leaves leather. There is a ectotrophic mycorrhiza. The plant uses the warmer climate of the near-surface air layers. The following features are adaptations to dry habitats ( Xeromorphosen ): The coarse leaves have a rolled- leaf edge and a shiny leaf surface.
The flowers are sun nimble, gay game " pollen - disk flowers ". The more than 100 stamens are secondarily caused by duplication ( a tuft corresponds to a stamen ). The flowers are only open in the sun and only at temperatures above 20 degrees. The outer stamens respond to touch its base with immediate, slow abduction. This mechanism serves einzustäuben pollen -seeking insects with pollen. This process is reversible. The petals have a strong UV reflection and are therefore visible to bees. The heat - and light-dependent opening and closing of the flowers can lead to spontaneous self-pollination. The flowers live for only one day. In the afternoon the petals fall off already. The flowering period extends from May to September. The fruits are dry capsules loculicidal who turn away unlike the flowers of light, so they are negatively phototropic. There is wind and random distribution and because of the stickiness of the seeds probably also a dissemination as Klebhafter. In addition, the seeds are distributed as Regenschwemmling. They are light to germinate. Fruit ripening from July to November.
Occurrence
This species is widespread in the Caucasus, Turkey and almost all of Europe except Iceland and Norway. As a location it prefers sunny and dry slopes, meadows, forest edges and rocks.
Use
The Yellow Rock Rose is used as a rock garden plant and used in Bach flower therapy.
Linguistic
Helianthemum is derived from the Greek name. helios is the sun, anthemon means flower. The word is derived from Latin nummularium nummulus that, small coin ' means ( the golden yellow flowers glow in the sunshine like gold coins). The storage for small coins is also nummularium. The English name of Rock Rose, Rock Rose, owes the Common Rockrose its occurrence on rocky slopes of the mountain range.
Subspecies
There are at least eight subtypes:
- Helianthemum nummularium subsp. berteroanum ( Bertol. ) Breistr. With occurrence of Italy to the south-east France.
- Bald ordinary Rockrose ( Helianthemum nummularium subsp glabrum ( WDJ Koch) Wilczek. ): With occurrence of central and southern Europe.
- Großblütiges ordinary Rockrose ( Helianthemum grandiflorum subsp nummularium ( Scop. ) Schinz & Thell. . ): With occurrence of central and southern Europe.
- Two-toned ordinary Rockrose ( Helianthemum nummularium ( L.) Mill subsp nummularium. ): Is widespread.
- Ovalblättriges ordinary Rockrose ( Helianthemum nummularium subsp obscurum ( Celak. ) Holub. ) In central (eg Austria ), Southeast, Southwest and Northern Europe.
- Helianthemum nummularium subsp. pyrenaicum ( Janchen ) Hedi: Is endemic in the Pyrenees.
- Helianthemum nummularium subsp. semiglabrum ( Badaro ) M. Proctor: With occurrence of Italy to the south-east France.
- Helianthemum nummularium subsp. tomentosum ( Scop. ) Schinz & Thell. With occurrence in southern Europe.
Varieties
There are also some varieties (selection):
- Helianthemum nummularium 'Rose Glory' with dark pink flowers.
- Helianthemum nummularium ' Annabel ' with double pink flowers.