Opopanax chironium

Opopanax chironium, also known as Chiron's Opopanax, is one of these superb umbellifers, somewhat in the line of the great fennel to which it resembles, however not or little used in gardens. This large perennial is truly spectacular, especially in June-July, when it emerges from the surrounding scenery by launching sturdy stems over 1.5 metres (5 feet) high carrying umbels loaded with numerous small yellow flowers. This plant, widely used in perfumery, only requires sunlight to flourish. It will be perfect in a naturalistic garden, a garden without watering, or in a large rockery among other giants.

Opopanax chironium is a large herbaceous perennial with a thick and woody stump belonging to the Apiaceae family (formerly Umbelliferae), just like celery, fennel, and carrot, which also bear inflorescences in umbels. This Opopanax is native to the Mediterranean region, but also to Syria and Lebanon. In France, it grows spontaneously on the arid hillsides of Provence, up to Castellane, but also in the departments of Hérault, Aude, and Pyrénées-Orientales.

The plant develops to form a bushy clump between 60cm (24in) and 1.5 metres (5 feet) high, sometimes more. It has a sturdy stump that produces large and long basal leaves, thickly divided into finely toothed lobes, of medium green colour with a hairy underside. In summer, between June and July, a solid stem 2cm (1in) in diameter, adorned with greatly reduced leaves, emerges from the foliage clump. It branches out and bears several compound umbels of numerous small yellow flowers. When the base of the stem is split, a fragrant sap escapes from the wound. By drying it in the sun, an oleoresin called opoponax is obtained, used in perfumery but also in aromatherapy.

Opopanax chironium is a beautiful plant that loves heat, for sunny beds or rockeries, in a rustic or naturalistic style. It pairs well with tall grasses (Stipa gigantea, Molinia caerulea subsp. arundinacea), but also with other giant and airy perennials like Ferula communis, bronze fennel, mulleins, Cephalaria gigantea, or tall thistles (Alpine blue thistle, Cardoon, Globe artichoke thistle), Pink or white Pampas grass, rose mallows, Helianthus salicifolius, and many more. It can easily be integrated into a dry garden or a large Mediterranean-style slope, accompanied by lavender, rockroses, and rosemary.