This plant grows as a weed in my garden, along with its relative Herb Robert. Shining Cranesbill is also sometimes called Shining Herb Robert. I say weed but I do tolerate it, especially where it grows out of a wall. It is in the geranium genus and as such has typical leaves and flowers, though the flowers are quite small.
The leaves do shine and thus its name, they also often have a red tinge and the petioles and stalks are also deep red, so even when not in flower, it is quite attractive. The leaves are deeply indented but have an overall round shape the indentations sub divide the leaf into five main lobes, each lobe also has smaller indentations. This species is far less hairy than other species in this group, what hairs it has are sparse and short. Presumably the shine is due to a thick cuticle and this is its way of preventing too much water loss from transpiration whereas other members of the group rely on hairs to do the same job….
The flowers are pink with five petals and a calyx in the form of capsule but also made up of five fussed sepals. Unlike many geranium species the petals do not show an indentation at the top. Quite often the flower stalk is bent, like a ‘U’ bend, I do not know why. It starts to flower in April, I saw some in flower on 19th of April 2018 in Coleford Gloucestershire in a crack between pavement and a wall. However 2018 was a slow Spring.
Several books and websites say that its seeds are ejected by a catapult mechanism. This is typical of many related species in this group. However I have not seen this and indeed the calyx remains intact and surrounds the seed capsule which would prevent such a process from happening. I think the seed capsule just falls off in the autumn and this plant does not have any special dispersal mechanism.
This is an annual plant, it is quite low growing and often grows where there are rocks or old walls. In these situations it can spread and sort of climb up if the rocks or wall have a suitable uneven, surface. It likes to grow in alkaline areas ie it is what is known as a calcicole..
I got this question from someone who reads this blog quite regularly.
‘I haven’t heard of this plant before and so may have falsely identified it as Herb Robert. Can you tell me if it grows widely in this country – would it be growing here in E Anglia, for example?’
So here is the distribution map from the BSBI.