GERANIUM FAMILY Click on any photo to enlarge it.
The Geranium family, includes the Geranium genus of more than 400 species, the Erodium genus of 60 species. and the Pelargonium genus of 200 species. The name of the genus Geranium comes from the Greek word geranos, crane and the name of the genus Pelargonium is from the Greek word pelargos, stork. The common name for geraniums is ‘Cranesbill’ after the fruit capsule which has a long column that looks like the bill of a crane as shown in this photo which illustrates the method of seed dispersal.
The column on the right in the photo is complete with the seeds at the bottom of the column. The column on the left has started to discharge its seeds. A strip of tissue called an awn is attached to each seed and the top of the column. When a seed ripens the awn suddenly breaks away from the column at its base and curls upwards throwing the seed outwards and away from the plant explosively.
A typical Geranium, Cranesbill ‘Johnson’s Blue’, has 5 free petals and 10 anthers (in 2 rows of 5) and 1 style with 5 stigmas.The petals are marked with guidelines for insects.
The original Pelargonium flowers, such as the Horseshoe Pelargonium shown here, did not have 5 identical petals. The 3 lower petals were narrower and unmarked compared with the 2 upper petals but many modern pelargoniums have had that characteristic bred out.
Bloody CranesbillGeranium sanguineum is a native wild flower found in dry grassy places on lime in flower from June to August. It is an open flower pollinated by various insects. Anthers release pollen before the stigmas are receptive.
Typical leaves of a Zonal Pelargonium. “Zonal” refers to a darkened band of tissue in the leaf. This pigment is pronounced and darkens as the plant ages. Also Zonal because their parentage includes Horseshoe Pelargonium which was introduced to Britain from South Africa in 1710 and used to create a huge number of cultivars in the second half of the 19th century. The typical zonal pelargonium, Pelargonium x hortorum now has symmetrical flowers, with all five petals being identical.
The Erodium genus has around 60 species. The common name is ‘Stork’s Bill’ or ‘Heron’s Bill’, taken from the shape of the mature seed pods. Erodium species are native to Europe, Central Asia, North and South America and Australia. Species have 5 petals with distinctive markings on the upper pair and 10 stamens with some reduced to staminodes, leaving 5 fertile stamens. There are a large number of cultivars for sale. They are most likely to be found in rock gardens or can be used in borders.