Taxonomy

Tradescantia (Andersoniana Group) ‘Domaine de Courson’

Tradescantia is a genus of 75 species of herbaceous perennial wildflowers in the family Commelinacae, after Commelina meaning dayflower, and are native to the New World from southern Canada to northern Argentina, including the West Indies. They have clusters of several flower buds which open progressively each day over several weeks between April and early July depending on the species. The flowers come in a variety of colours from white through various shades of blue, purple and pink to almost dark red. They are characterised by having three sepals, three petals and six stamens with fuzzy filament hairs topped by bright yellow anthers.

Some spiderworts are natural Geiger counters. The fuzzy filament hairs in the flower change from blue to pink when exposed to low levels of radiation.

Tradescantia virginiana

The original plant brought back to England by John Tradescant from his expedition to Virginia in 1629 is believed to be the type species Tradescantia virginiana, but another 17 closely related species have since been discovered and named including the widely distributed Tradescantia ohiensis, Tradescantia bracteata, Tradescantia subaspera, Tradescantia ernestiana and Tradescantia ozarkana.

Tradescantia ohiensis

When in close proximity, as in domestic gardens, these winter hardy Tradescantias from North America USDA Zones 4-9 are very promiscuous and have spawned dozens of hybrids. The American botanist Edgar Shannon Anderson conducted a ten year extensive study in the 1920’s and 30’s and this collection of hybrids is now referred to as the Andersoniana Group (often referred to with the invalid name Tradescantia × andersoniana.) This is a group of interspecific hybrids believed to have developed from Tradescantia virginiana, Tradescantia ohiensis and Tradescantia subaspera which have overlapping ranges within continental North America. However, it has since been discovered that other species of Tradescantia are also known to hybridize such as T. ernestiana and T. ozarkana which have increased the range and scope of the Andersoniana Group. All these hybrids are clump-forming herbaceous perennials, with individual cultivars mainly differing in height, flower colour, leaf colour and leaf form.

Most people think of Tradescantias as familiar house plants and indeed, the remaining 57 species of Tradescantia in the genus, often referred to as the ‘Inch Plant’, are tender, tropical types from Mexico and South America and are not covered by this website which is only concerned with the North American winter-hardy species.

Tradescantia zebrina – Photo by Rachel Claire on Pexels.com