Photo a dome-shaped inflorescence of small, white, 5-petaled flowers. The woody stems have opposite branches, meaning the leaves have an opposite arrangement, which is typical of Viburnum. Photo by Scott Zona CC BY-NC 4.0.

I'll finish up Viburnum week with a portrait of V. prunifolium, a species in bloom right now, not far from where I live. As the name suggests, the leaves look like those of Prunus, the cherries, but as the leaf arrangement is opposite, you’d never mistake this plant for a Prunus. #Viburnaceae 🌱

Photo of a hand cradling a flat-top cluster of small, fleshy fruits. Most of the fruits are pink, but about a third of the fruits are dark blue. Photo by Scott Zona CC BY-NC 2.0.

The fruits of many Viburnum species undergo an intermediate color change between green and fully ripe. These fruits of V. nudum ripen from green through pink to dark blue. The intermediate color may provide additional visual cues to avian seed dispersers. #Viburnaceae #Botany 🌾🧪🌱

Photo of a hand holding a shiny obovate, serrate leaf. In the axils of the midvein and secondary veins, there are small, blister-like areas—indicating the sunken domatia that occur on the underside of the leaf in those locations. Photo by Scott Zona CC BY-NC 2.0.

Viburnum species may also have domatia on the leaf. Domatia are pockets, pits or tufts of hair in which beneficial mites reside. In Viburnum awabuki the domatia are so prominent in the axils of the main veins that they are visible from the upper surface of the leaf. #Viburnaceae #Botany 🌾🧪🌱
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Close-up photo of the petiole of a leaf. The petiole is red and has two clavate, stalked glans just below the junction of the petiole and blade.

If you look closely at the petiole of Viburnum trilobum (📷: Peter Zika CCBYNC4) to see the extrafloral nectaries just below the blade. Extrafloral nectaries are common in Viburnum petioles, but they also occur as marginal teeth or embedded in the blade. #Viburnaceae #Botany 🌾🧪🌱

That ladder-like venation pattern is genuinely beautiful — nature's geometry at its finest. And the nod to Cinnamomum in the epithet makes sense when you see both leaves side by side. Taxonomy telling a visual story. 🌿
#Viburnaceae #Botany #PlantScience #GardenNerd

Photo of leafy, woody shoots with opposite leaves. Each leaf has three main veins and ladder-like transverse secondary veins. An old inflorescence is front and center. Photo by Scott Zona CC BY-NC 2.0.

Viburnum cinnamomifolium has leaves with 3 main longitudinal veins & transverse secondary veins that give an attractive, ladder-like pattern to the leaves. The species epithet likens the leaves to those of the unrelated Cinnamomum (Lauraceae). #Viburnaceae #Botany 🌾🧪🌱

Photo of leafy, woody shoots. The leaves are opposite, narrowly elliptical, and have strong, net-like venation. Photo by Scott Zona CC BY-NC 2.0.

Viburnum leaves are sometimes more interesting than the flowers (yep, I said it!), & many species are cultivated for their foliage. Viburnum rhytidophyllum has sunken venation that gives the leaves an attractive texture. “Rhytidophyllum” means “wrinkled leaf.” #Viburnaceae #Botany 🌾🧪🌱

Photo of leafy shoots with serrate leaves and a cluster of tiny, white flowers. The peripheral flowers in the cluster are greatly enlarged, white, showy but sterile. Photo by Scott Zona CC BY-NC 2.0.

Some species of Viburnum have, like Hydrangea, inflorescences of both small fertile and large sterile flowers. Inflorescences of Viburnum plicatum var. plicatum have peripheral flowers that attract pollinators to the tiny, fertile flowers. #Viburnaceae #Botany 🌾🧪🌱

Photo of leafy shoots with coarsely serrate leaves and a cluster of small, white, bowl-shaped flowers.

Viburnum flowers are typically small & white, & the anthers are fused to the corolla. They are easy access for just about any insect. This is Viburnum phlebotrichum (📷: Timur Kalininsky CCBY4) of Japan, whose bowl-shaped flowers are great for pollen- & nectar-eaters. #Viburnaceae #Botany 🌾🧪🌱

Photo of leafy shoots with serrate leaves and a cluster of small, white, bowl-shaped flowers. Photo by Scott Zona CC BY-NC 2.0.

The genus Viburnum has over 200 species, mostly in the northern temperate zone. They have opposite leaves, dome-shaped panicles of small flowers & red, blue or black drupes. This is Viburnum rafinesqueanum of eastern N. America. #Viburnaceae #Botany 🌾🧪🌱

Photo of a flat-topped inflorescence of small, fertile flowers surrounded by a few, large, sterile flowers. Photo by Scott Zona CC BY-NC 2.0.

Like Hydrangea, some Viburnum cultivars, such as V. plicatum var. plicatum 'Summer Stars', also have the lacecap inflorescences. Remarkably, Viburnum & Hydrangea are not close relatives (separate orders)! Lacecap inflorescences evolved at least twice! #Viburnaceae #pollination #Botany 🌾🧪🌱