Tritonia disticha subsp. Rubrolucens

Red Montbretia Iridaceae

A handsome South African cormous perennial producing a strong fan of upright, sword-shaped leaves, followed in mid to late summer by wiry, branching stems carrying a succession of open, funnel-shaped flowers. The flowers are typically clear pink to rosy-pink, about 2 cm across, and are borne in elegant one-sided spikes, giving the plant a considerably more refined appearance than the rather generic name “montbretia” might suggest. The RHS gives an eventual height of around 50–100 cm, with a very narrow spread. 

It is a plant of summer-growing, winter-dormant habit, native to southern Africa, where it has a wide distribution including KwaZulu-Natal, Mpumalanga, the Eastern and Western Cape, Free State and Eswatini. It is regarded as Least Concern in South Africa. 

Growing conditions: Give it full sun and a sheltered position in fertile but very free-draining soil. Sandy or gritty soils are particularly suitable, and although it will tolerate acid, neutral or alkaline conditions, winter drainage is the important consideration. In wetter parts of Britain, planting with the corms raised slightly or incorporating plenty of grit can be beneficial. The RHS recommends a deep, dry winter mulch and avoiding excessive winter wet. 

In colder areas, the corms can be lifted once the foliage has completely died down, although in a well-drained, sheltered position it is generally hardy enough to remain outside in much of Britain. The RHS rates it H4, approximately –10 to –5°C. 

Nomenclature

The currently accepted species is Tritonia disticha (Klatt) Baker, with rubrolucens treated by Kew as a synonym rather than an accepted subspecies. The subspecies combination Tritonia disticha subsp. rubrolucens (R.C.Foster) M.P.de Vos was published by M.P. de Vos in 1983. Its basionym is Tritonia rubrolucens R.C.Foster, published in 1936. 

Height: 50–100 cm
Spread: 10–20 cm
Flowers: July–September
Position: Full sun
Soil: Fertile, sandy or gritty, very well drained
Hardiness: H4 (–10 to –5°C)

Dormancy: Winter

A particularly good late-summer bulb for a sunny, well-drained border, where its clear pink flowers and narrow, upright habit make a useful contrast to heavier summer perennials.