Odd hedge in a Córdoban botanic garden

The Real Jardín Botánico de Córdoba in southern Spain, is a long, thin botanic garden. With a rather formal teaching garden and specialist collections representing the flora of the Canary Islands and fossil plants, its beauty and attraction are perhaps not grasped immediately.

That scholarly approach is no doubt a consequence of being run by IMGEMA, translated roughly as the Municipal Institute of Environmental Management. That connection also gives it a powerful raison d'être, something missing from otherwise quite pretty botanic gardens.

So within its 7.5 hectares you'll find a paleobotanical museum, seed bank and education facilities. You'll also find some hedges. Like almost every garden in this region (Andalusia) it has garden beds bound by low hedges.

Here though the hedges serve another purpose, to trial and display interesting plants. In addition to the locally familiar box and myrtle, here we have pomegranate and even celery.

The hedge that caught my eye (below) was created with Spurge Olive, Cneorum tricoccon. To be fair, this plant isn't quite working as a hedge, yet, but it's an interesting choice. The Spurge Olive is an uncommon plant in western Europe, listed as vulnerable in the IUCN (International Union for Conservation of Nature) Red List.

There are only two species of Cneorum, one from Canary Islands (unfortunately I didn't check if it was featured in the Real Jardín Botánico display), the other from Mediterranean Europe.

As you can see in this map from the Red List page, it occurs naturally in France, Italy and Spain, and although not native to the Cordoba region it is found in nearby Granada and the Andalusian coast.

In the wild, along sandy and rocky tracks, this species gets to just over a metre high according to Tony Hall, in his Wild Plants of Southern Spain. The red fruits apparently blacken when ripe. I wouldn't eat them, although lizards and in more recent times, pine martens, do. According to HortFlora, the leaves and fruits are used locally as a purgative (although more attractively, at their red stage they are applied as a rouge).

The three-lobed fruits are distinctive, and rouge-red when semi-mature, but the three-lobed yellow flowers are equally intriguing. Flowers are either male or hermaphroditic (that is, with male and female parts, like most flowers), with the pollen in the male flowers more 'fertile'. The open flower here is a hermaphrodite.

You'll also notice what look like 'gland' dots or dimples on the leaves, typical of the family in which it now resides, the Rutaceae. Think correa and citrus.

In Cneorum these glands are often 'inconspicuous', perhaps one of the reasons it used to be in its own family, the Cneoraceae (sometimes with another genus, Harrisonia). The move to Rutaceae is a good one in my view because except in exceptional cases (e.g. Entwisleaceae...) a family with one genus doesn't give you much information anyway, and that's what classifications are for.