Botanist's Lens: Evening Primrose, Sweetshrub, & Dogwoods

Updated: May 24

Flowers, florets of simple and complex forms.

Evening Primrose (Oenothera speciosa)

Flowers come in numerous shapes, sizes and color. Some that appear simple are sometimes multi-fold complex in their anatomical features and their origin. For eg. an Evening Primrose's (Oenothera speciosa) pink flower and Chinese Sweetshrub (Calycanthus chinesis) might appear similar in that the outer layers have simple 4-7 petals. Both are whitish pink, have no fragrance, and are delicate and solitary in appearance.


Evening Primrose (Oenothera speciosa)

However, as simple as the Primrose flowers are with a single layer of petals, the Calycanthus chinensis are far too complex. Not only is it a rare plant in the wild, what appears as petals are actually a layer of tepals. They have not one, but two layers of tepals: a white outer layer and an inner smaller yellow layer.


Chinese Sweetshrub (Calycanthus chinensis or Sinocalycanthus)

Sweetshrub (Calycanthus chinensis (or Sinocalycanthus) is a distinct woodland shrub that flowers in May. "While presently established in several public gardens and a few private gardens in England, Holland, Canada, and the United States, Sinocalycanthus is largely unknown in botanical and horticultural circles". Source


Arum maculatum

Another complex flower is of the Arum family, Arum maculatum. Here the flowers are borne on an inflorescence stalk called "spadix," and it is enclosed in a hood shaped spathe. The flowers actually are tucked inside at the bottom on the spathe, with a ring of male flowers at the base and female above.


Too complex? Or are the precious flowers of Dogwood even more so?


Dogwood (Cornus 'Rutpink')

Cornus species, or Dogwoods, are known for their showy flowers have flowers that are almost inconspicuous and complex. What appears as petals are true bracts (modified leaves) with true flowers tucked inside at the center in a pinchusion shape. Featured is a variety of Cornus 'Rutpink' a new variety from Rutgers University. It is not a hybrid, but a species selected after many generations of intercrossing different forms.


Flowers, florets, inflorescence, simple, complex or inconspicuous, flowers come in numerous shapes and sizes. Look up close though, what sometimes seems simple is sometimes far too complex. But simple or complex, their purpose is the same, to propagate and help the species thrive.



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