Hesperantha: how to grow and when to plant hesperantha

By John Grimshaw

Published: Thursday, 08 September 2022 at 12:00 am

More than 30 years ago I was high in the alpine zone of Mount Kilimanjaro in Tanzania, when I came across a tiny, pink-flowered bulb, standing just a few centimetres above the dry soil. It was Hesperantha petitiana, the northernmost representative of a genus of more than 80 species, the majority of which are endemic to the winter-rainfall areas of southern Africa’s Western Cape, where the commoner species can sometimes be found in enormous numbers.

Often inconspicuous during the day, hesperanthas open in the afternoon or evening – a habit that suggested their name, which means ‘evening flower.’ Although the Western Cape species have been cultivated on and off for the past 200 years, they are very seldom seen outside specialist collections, a shame as many are beauties, including the yellow and chocolate Hesperantha vaginata, the pink Hesperantha pauciflora and Hesperantha cucullata with pink-backed flowers that open white in late afternoon. A few tens of thousands of them shimmering among the annuals and other little bulbs in southern Africa’s Namaqualand is a wonderful sight.

© Jason Ingram

For the majority of gardeners, however, Hesperantha means just one species, the large and splendid Hesperantha coccinea, which is something of an anomaly in the genus and indeed was long-placed as the single species of the genus Schizostylis. It comes from another centre of diversity in the genus, the Drakensberg range of eastern South Africa, where about 14 species occur. Most are summer-flowering, opening their pink flowers in the daytime; of this group only Hesperantha baurii and Hesperantha huttonii are in cultivation. Like the Western Cape species they grow from corms, renewed each year, with the plants undergoing seasonal dormancy in the cold, dry winter. In the wild, their habitats are usually damp in summer, and this is preferred in cultivation.

How to grow Hesperantha

When to plant hesperantha

Best grown from seed sown in late summer. Supplemental lighting is beneficial in dull weather. In their wild habitat, they mostly flower from August to September. In the wild, where its range stretches throughout the mountains of eastern South Africa into Zimbabwe, Hesperantha coccinea seems almost invariably to grow alongside streams, often threading its stolons through cushions of wet moss. Fortunately, the requirement for running water doesn’t extend to gardens, where Hesperantha coccinea will grow in any reasonable soil, almost anywhere in the UK and Ireland. Its great value is its predominantly autumn-flowering period, producing spikes of beautiful satiny flowers over a long season from August into winter: if there is no frost they may go on into December and even January.

© Bob Gibbons/Alamy

Where to grow hesperantha

Hesperantha coccinea is best grown in rich, moist conditions in full sun. It can survive in even quite dry places but will not perform well. The eventual height of most cultivars will vary depending on the growing conditions. Give these plants a sunny, well-drained position on a rock garden. Standing only 15-30cm high they should not be swamped by taller plants.

Dividing hesperantha

For best results, lift, divide and replant tired clumps into enriched soil every two to three years, and mulch with good compost. The stoloniferous habit can take plants beyond their bounds, and pieces will remain when clumps are lifted. Weed these out by hand if necessary. Tatty, overwintered foliage can be sheared or strimmed off in spring prior to mulching.

In really cold areas adding a thick mulch in late autumn will be beneficial, but in the current climate Hesperantha coccinea is generally hardy in the UK and Ireland and the milder parts of western Europe and western North America.

The winter-growing species from the Western Cape, such as Hesperantha vaginata and Hesperantha pauciflora, are more challenging. They need frost-free, cool but well-ventilated, bright conditions, in a well-drained gritty compost, kept moist in winter but dry in summer.

© Tony Baggett/Alamy

What to combine with hesperantha

Hesperanthas work well in the garden when combined with other plants. Weave Hesperantha coccinea among early flowering plants to provide late-season interest, perhaps over a clump of daffodils or around an iris in wetter places. In my dry garden it’s not very happy, but a patch of the rich-red (neither scarlet nor crimson is probably the best description) Hesperantha coccinea ‘Major’ often manages a few stems to complement the late-flowering, soft yellow Crocosmia ‘Ellenbank Canary’ and blue-mauve Symphyotrichum ‘Little Carlow’ behind. White or pale-pink cultivars can look good with the darker colchicums, and the foliage of each can fight it out in spring.

A well-nourished row of Hesperantha coccinea in a cutting garden will provide a long season of flowers into late autumn or early winter; robust corms could be planted in a large pot for late-season conservatory decoration. Remove seedheads if not frosted to avoid seedlings getting in among named selections.

Hesperantha pests and diseases

Pests and diseases are unusual in hesperanthas, but virus can cause streaking in the flowers.

The best hesperantha to grow

Hesperantha coccinea ‘Major’

The best red-flowered cultivar – perhaps the best of all – but there is some variation in its stocks. The 6cm rounded flowers of rich, almost coppery red, have a beautiful sheen that catches the sun. 50cm x 30cm. AGM. RHS H4, USDA 7a-9b.