INTERMEDIATE EVENING-PRIMROSE

Oenothera × fallax

Willowherb Family [Onagraceae]

month8jun month8june month8jul month8july month8aug month8sep month8sept

status
statusZnative
 
flower
flower8yellow
 
morph
morph8actino
 
petals
petalsZ4
 
type
typeZspiked
 
stem
stem8round
 
smell
smell8fragrant
fragrant
rarity
rarityZuncommon
 
sex
sexZbisexual
 

Photo: © Phil Smith
The Wildflower book by Blamey Fitter & Fitter claim that the tips of the unopened flower buds are red, but they look green to your Author...


Photo: © Phil Smith
Typical of Evening-primroses growing form: the yet to open flowers are at the top with their 4 long sepals surrounding the longish flower bud. The usually few opened flowers are just below them, often with their 4 sepals folded down out of the way. The opened flowers are usually only few in number whilst the ±cylindrical fruits below them accumulate in number from about about half-way up the main stem.

The flower buds of Intermediate Evening-Primrose are wide red stripes with pale-green narrow stripes on the outside of the 4 sepals, with each sepal having two broad red stripes near the edges separated by a thin pale green stripe. Where adjacent sepals meet is a further pale-green narrow stripe. Altogether making 8 narrow pale-green stripes separating 8 wider red stripes.



Photo: © Phil Smith
The flowers themselves are medium in size, with petals 2 to 3 cm long. But the anthers and the stigma are held aloft at roughly the same level. In this regard it differs from one of its parents (Large-Flowered Evening-Primrose) in having a shorter style.


Easily confused with : other Evening-primroses (Oenothera) species.

On the Sefton Coast it presumably partakes of the wild orgies indulged by most of the Evening-primrose species there, making crosses and back-crosses and participating in the hybrid swarm of Evening-primroses there residing. Nowhere else in the UK does this happen (or at least that is what your Author has been led to believe).

Although fairly rare, even on the Sefton Coast where rampant interspecies crossing occurs, this Intermediate Evening-primrose is a fairly stable hybrid between Large-Flowered Evening-Primrose (Oenothera glazioviana) and Common Evening-Primrose (Oenothera biennis) managing to persist as this hybrid.

Most Evening-primroses are fragrant, but are much more fragrant in the evening, hence their name.

Strangely enough, unlike most (all?) other Evening-Primroses, this one (although a hybrid) is native (whereas all the rest(?) were introduced and naturalised in the UK and originate from America). This probably reflects the fact that this Evening-Primrose is a stable hybrid and can reproduce truly.

The leaves of Intermediate Evening-primrose are crinkled and have a red mid-rib.

Intermediate Evening-Primrose is the hybrid between a female Large-Flowered Evening-Primrose (Oenothera glazioviana) and a male Common Evening-Primrose (Oenothera biennis) and is a stable hybrid, remaining constant in appearance. It can sometimes be found in the absence of either parent.

The reverse situation - the hybrid between male Large-Flowered Evening-Primrose (Oenothera glazioviana) and a female Common Evening-Primrose (Oenothera biennis) does not remain constant in appearance. It differs in that the petals are often longer than 3cm and the style often extending beyond the stamens. This one is sometimes treated as a species (although Prof. Clive Stace does not say what the species name is). Backcrosses to both parents occur (your Author is not sure what exactly that means - he thinks it means a backcross can revert to either one of its parents).

Reciprocal crosses between Large-Flowered Evening-Primrose (Oenothera glazioviana) and the segregate (a species which has been split from another taxon) Small-Flowered Evening-Primrose (Oenothera cambrica) produces a hybrid with yet different feature combinations. The equivalent hybrid, but with a female Large-Flowered Evening-Primrose (Oenothera glazioviana), is called Hybrid Evening-primrose (Oenothera britannica).


  Oenothera x fallax  ⇐ Global Aspect ⇒ Onagraceae  

Distribution
 family8Willowherb family8Onagraceae

 BSBI maps
genus8Oenothera
Oenothera
(Evening-Primroses)

INTERMEDIATE EVENING-PRIMROSE

Oenothera × fallax

Willowherb Family [Onagraceae]