Each fall, we sing the praises of fall allium and autumn crocus blooms. This year, however, a special mention must be made for the glorious gladiolus! Especially the delicate, 4-inch, salmon pink flowers of the salmon gladiolus (Gladiolus oppositiflorus spp. salmoneus).

Hailing from areas of the cold, higher elevations of the Drakensberg Mountains of South Africa that get significant summer rainfall, this beautiful, wild species has proven amazingly hardy in the Chicago Botanic Garden’s Graham Bulb Garden over the last five years—including a couple of winters with record-setting cold temperatures!

Two characteristics of its native habitat nominated the gladiolus for trial at the Garden: first, it is a winter-growing bulb in South Africa, which translates to summer growth in North America. Second, this plant thrives in moist soils in grassy areas—it was perfect for the site we chose in the Bulb Garden.

Based on its initial success in our plant trial program, other gladioli (also currently in full flower) were added to the trials. We’ve also discovered that these wild species thrive and multiply in well-drained soils (but do not tolerate flooded soils). The beautiful, red-flowered Gladiolus saundersii is also native to the Drakensbergs, but from a higher, colder, and snowier habitat. And a third selection is probably a close relative of Gladiolus dalenii var. primulinus. Discovered in an old, abandoned farmstead in North Carolina, and sold under the name ‘Carolina Primrose’, this gladiolus generally blooms in July and early August. All came through some record-breaking cold winters. 

It’s not easy to find commercial sources for these bulbs, but it’s well worth the effort to obtain an elegant, refined, fall-flowering, and hardy gladiolus.