HERB-ROBERT

STINKING BOB

Geranium robertianum

Crane's-bill (Geranium) Family [Geraniaceae]  

month8apr month8april month8May month8jun month8june month8jul month8july month8Aug month8sep month8sept month8Oct month8Nov

status
statusZnative
 
flower
flower8pink flower8lilac
 
inner
inner8yellow
 
inner
inner8orange
 
inner
inner8brown
 
morph
morph8actino
 
petals
petalsZ5
 
stem
stem8round
 
smell
smell8stinks smell8smell smell8pongs smells8nauseous
pongs

10th May 2015, extinct platform, extinct railway, Radcliffe, Lancs. Photo: © RWD
Likes to spread along walls, but never reaching higher up than maybe 1.5m.


25th May 2005, Reddish Vale, Greater Manchester. Photo: © RWD
Growing at the foot of a wall is favourite.


11th May 2008, The Old Pint Pot, The Crescent, Salford, Lancs. Photo: © RWD
The stems are hairy. Leaves fern-like but are asymmetric.


18th July 2007, Croker, Staffordshire. Photo: © RWD
White forms are quite common.


9th June 2004, Monsal Dale, Derbyshire. Photo: © RWD
It has a straggly appearance.


12th May 2020, a garden, Walkden, Gtr M//cr. Photo: © RWD
The leaf stalks and flower stalks have long and shorter hairs. The leaves have hairs too (best seen on the leaf at far right). The leaves are ternate to palmate in shape with 3 to 5 leaflets.


12th May 2020, a garden, Walkden, HGtr M//cr. Photo: © RWD
The leaves end in an acuminate (shortly-pointed) tip. Long and shorter hairs on the sepals too; shorter ones on the top surface of the leaves. The leaves are cut less than 3/4 of the way to their base.


24th April 2004, Rochdale Canal, Cragg Vale. Photo: © RWD
The leaves have slightly alternate broad branches giving it an asymmetric look.


25th June 2004, Grindleford, Derbyshire. Photo: © RWD
Both fern-like leaves and stems readily redden in strong sun or when stressed.


4th July 2006, Rochdale Canal, Slattocks. Photo: © RWD
The flowers have five rounded un-notched pink petals. The 'bills' prominent. Almost everything has gone bright red here apart from the petals.


13th June 2008, Walkden, Greater Manchester Photo: © RWD
The white form is otherwise no different to the pink form. 10 stamens bearing yellow pollen.


13th June 2008, Walkden, Greater Manchester Photo: © RWD
It has five pink anthers surrounding another five stamens with yellow-pollened anthers with a single style lurking somewhere in the centre.


11th May 2008, The Old Pint Pot, The Crescent, Salford, Lancs. Photo: © RWD
Many pink-petalled Herb-robert flowers have white radial streaks.


11th May 2008, The Old Pint Pot, The Crescent, Salford, Lancs. Photo: © RWD
Books state that Herb-Robert lacks central notches in the petals, but plainly there are a pair of nicks on each side of some petals of this specimen.


11th May 2008, The Old Pint Pot, The Crescent, Salford, Lancs. Photo: © RWD
There are two circles of 5 anthers: and outer circle of larger ones and an inner circle of smaller dark-brown ones which have opened displaying their bright-yellow pollen. In the centre is a pink style...


12th May 2020, a garden, Walkden, HGtr M//cr. Photo: © RWD
The petals are usually deep-pink and somewhere between 8 and 14mm long. They are rounded at their apex.
The 5 sepals have 3 green ribs interspersed by 2 almost white grooves. The sepals have a long cylindrical (but very narrow) extension at their tips.
An as-yet un-opened sepal cup is on the left.


12th May 2020, a garden, Walkden, HGtr M//cr. Photo: © RWD
The ends of the long thin extension at the end of the sepal are tipped red.
At the junction of two (shortish) flower stalks are some tiny, triangular-shaped pale-green bracts.
The hairs are of two or three lengths, that's the long and short of it... Those on the sepal cups usually being longer (and often tapering from a wider start) than those on the stalks.


12th May 2020, a garden, Walkden, HGtr M//cr. Photo: © RWD
See the captions immediately above.


12th May 2020, a garden, Walkden, HGtr M//cr. Photo: © RWD
The five outer black anthers on this specimen are the colour of the casing around as-yet un-opened stamens. The inner 5 stamens are smaller and have opened.


12th May 2020, a garden, Walkden, HGtr M//cr. Photo: © RWD
Five larger un-opened stamens surround the yellow pollen of the 5 smaller inner stamens.


12th May 2020, a garden, Walkden, HGtr M//cr. Photo: © RWD
The larger and outer anthers (orange here) seem to only open later than the smaller and inner 5 which here have opened and displaying their yellow pollen.


12th May 2020, a garden, Walkden, HGtr M//cr. Photo: © RWD
Bird's-eye view. 5 as yet un-opened orange stamens surround 5 opened formerly brown-cased stamens with yellow pollen. In the centre, usually hidden, is the here six(?) star stigma. Your Author would have expected the stigma to normally be in 5 parts. But Herb-robert is notoriously variable in characteristics.


18th September 2008, Mills Hill, Rochdale Canal. Photo: © RWD
Bird's-eye view. A totally prostrate form is not un-usual. This specimen is sitting at the edge of the canal towpath partly overhanging the water. Obviously a little stressed-out judging by its deep-red parts.


18th September 2008, Mills Hill, Rochdale Canal. Photo: © RWD
Having both reddened and green leaves with those inbetween being a dirty green colour (Subtractively, red plus green is brownish).


Some similarities to : Little Robin (Geranium purpureum), but Little Robin grows only in the South West and has redder flowers, is taller than Herb-Robert and the leaves are more narrowly cut.

Distinguishing Feature : Once you have found this plant you are unlikely to mistake it for anything else. Unless you come across it in the prostrate form where it seems to be a different plant, but closer inspection will reveal mostly the same characteristics.

No relation to : Herb-Bennet nor with the much rarer Herb-Paris [plants with similar names]

One of the longest flowering members of the Geranium Family, flowering for 8 months. It is very hardy and extremely weedy, being very difficult to eradicate from a garden once it has found its way in. The small pink flower about a half-inch across has five petals which if notched at all are slightly nicked twice on either side of the centre-line rather than on the centre-line as most other notched petals. There is also a white petalled form which occurs quite frequently. The pollen is yellow.

Herb-Robert is ubiquitous throughout the UK. Normally it is quite sticky and smells horribly if crushed, hence the nick-name 'Stinky Bob'. The leaves are skewed fern-like in appearance. The whole plant has a tendency to go red in prolonged strong summer sunshine. It is native and grows in hedge banks, woods, cracks in pavements and on mountain screes. The prostrate form, which grows on shingle or between cracks in stones, is usually hairless and more often red than the straggly form.

It is so variable in appearance that some taxonomists split it into two sub-species, ssp. celticum and ssp. martiimum (the seaside version) but there is so much variation between these that any such a distinction is abandoned by other taxonomists.


  Geranium robertianum  ⇐ Global Aspect ⇒ Geraniaceae  

Distribution
family8Cranesbill family8Geranium  family8Geraniaceae
 BSBI maps
genus8geranium
Geranium
(Crane's-bills)

HERB-ROBERT

STINKING BOB

Geranium robertianum

Crane's-bill (Geranium) Family [Geraniaceae]  

WildFlowerFinder Homepage