Blooming Beautiful: An introduction to South Africa’s winter rainfall bulbs

Unparalleled Diversity

Above: Autumn flowering of Brunsvigia bosmaniae flowering en masse just outside Nieuwoudtville.

South Africa’s winter rainfall zone is home to one of the richest assemblages of bulbous plants on Earth, comprising more than 2 100 species. From the succulent Karoo of the Richtersveld to the fynbos of the Cape Peninsula, this area encompasses a diverse range of ecosystems unparalleled in few other parts of the world.

Waterwise Beauties

Above: Moraea gigandra blooming in cultivation at Kirstenbosch National Botanical Gardens.

Many of these stunning bulbs are very easy to grow, bringing spectacular blooms to the indigenous garden. They are highly waterwise as a result of their summer dormancy, requiring no water when this precious resource is most in demand. Here on the BotSoc Blog we take a look at a few of the more easy to grow genera suitable for the novice bulb grower.

The Genus Freesia

Known the world over for their elegant blooms and exquisite fragrance, Freesia need little introduction. They are a member of the Iridaceae family with 16 species in the genus from the southwestern Cape to tropical Africa. Freesias like to be grown in a sunny or lightly shaded position in a light, slightly acidic growing mix of potting soil and coarse river sand.

Plant the corms during autumn at 2-3cm in depth. Water heavily once and then around twice weekly once the shoots appear. Freesia alba is one of the easiest species to grow. Freesia caryophyllacea is known for its heavy scent and yellow and white blooms.

The Genus Lachenalia

Above: Lachenalia quadricolor flowering at one of its last remaining habitats on the Cape Flats.

Coming in a stunning range of colours from yellow to turquoise, Lachenalia are some of the most no nonsense bulbs one can grow. The genus is endemic to Namibia and South Africa with a total of around 120 species, most of which are winter growing. They grow best in pots in a sharply draining growing medium of coarse river sand with a 5cm layer of compost in the bottom of the pot.

Bulbs should be planted in the autumn 1-2cm below the surface and after an initial drenching, should not be watered again until the new shoots appear. Try growing Lachenalia quadricolor, easily recognised by its traffic light coloured blooms. Lachenalia flava with its deep yellow blooms is just as easy and rewarding. Hailing from the West Coast, the turquoise blooms Lachenalia viridiflora are hard to miss.

The Genus Moraea

Above: Critically Endangered Moraea aristata in bloom.

Members of the genus Moraea are also known for their spectacular blooms that come in a myriad of different colours. Quite a number of species originate from lowland renosterveld and have become highly threatened in the wild due to habitat loss from transformation for agriculture. The majority are relatively easy to cultivate however. All the winter growing Moraea enjoy a sharply drained growing medium and to be drenched two to three times per week during the growing season.

The most prized in cultivation are the Peacock Moraeas. One of the easiest species to cultivate is Moraea aristata, which is Critically Endangered in the wild having lost most of its original habitat underneath Cape Town’s Southern Suburbs. Coming from renosterveld vegetation in the Overberg, Moraea elegans also has very striking blooms.

The Genus Nerine

Above: Nerine sarniensis in bloom at Harold Porter National Botanical Gardens, Bettys Bay, Overberg.

Coming into bloom during autumn when little else is in flower in the Cape, Nerines are another highly rewarding bulb genus to grow. They grow well both in containers as well as in rock gardens and herbaceous borders. In autumn they should be given an initial drenching of water to stimulate flowering, but then should not be watered again until the leaves emerge later in the season. Thereafter they should be watered weekly. Nerine humilis produces attractive pink blooms. Nerine sarniensis has perhaps some of the most spectacular flowers of the genus, producing large glistening red or pink flowers.

The Genus Watsonia

Above: The dwarf Watsonia coccinea comes in a variety of different flower colours.

Members of the genus Watsonia are ideal for planting en masse in the garden for spring and early summer displays. There are also some smaller members of the genus that are better suited to container growing. They should be planted in full sun in autumn at 2-5cm in depth depending on the species and size of the corms. Watsonia borbonica is one of the larger species and does well planted en masse. The diminutive Watsonia coccinea has a variety of different colour forms, growing well in deep pots.

Further Reading

Duncan, G. (2010) Grow Bulbs, Kirstenbosch Gardening Series, South African National Biodiversity Institute, Cape Town, South Africa.

Manning, J. Goldblatt, P. Snijman, D. (2002) The Colour Encyclopaedia of Cape Bulbs, Timber Press, Cambridge, United Kingdom. ISBN 0-88192-547-0.

Autumn Colours: A closer look at Brunsvigias

The long hot and dry summers are the toughest time of year in the Cape. There is little rainfall and temperatures can be high. Many bulbous Cape plants adapt to this time of year by entering a time of dormancy, tucked safely underground and sleeping until the next rain comes during early autumn.

The genus of plants that heralds the coming of autumn most strongly in the Cape is Brunsvigia, known for their spectacular blooms. The first rains of autumn trigger these vast bulbs to break their dormancy, producing huge blooms emerging from the dry earth when little else is in flower. Here on the BotSoc Blog we take a closer look at some members of the genus that grow in South Africa’s winter rainfall zone.

Brunsvigia striata

Above: Brunsvigia striata. 

Also known as the kleinmaartblom or seeroogblom in Afrikaans, Brunsvigia striata is one of the more diminutive members of the genus. It is widespread across the Cape Floristic Region, growing from the Bokkeveld Mountains southeast to Cape Infanta at the mouth of the Breede River in the Overberg and eastwards to Steytlerville in the Eastern Cape. Brunsvigia striata grows on rocky ground on mountain slopes, on dolerite derived and humus rich soils. Flowering takes place from late February to April, peaking during March.

Brunsvigia orientalis

Above: Brunsvigia orientalis in bloom after fire, Cape Peninsula.

This huge member of the genus is a case of mistaken identity if there ever was one. Its species epithet ‘orientalis’ means ‘of the Orient’, which is in reference to the belief that Brunsvigia orientalis originated in India. In fact, this proudly South African geophyte is common throughout the country’s winter rainfall zone. It is distributed from Vanrhynsdorp in Namaqualand southwards to the Cape Peninsula and eastwards to Cape St Francis in the Eastern Cape. Brunsvigia orientalis grows on sandy flats and dunes and is also occasionally associated with granite derived soils. Flowering takes place from February to April, with increased flowering taking place in response to late summer and early autumn rain.

Brunsvigia josephiniae

Top & Above: Brunsvigia josephiniae in flower at Karoo Desert National Botanical Gardens.

The colossal Brunsvigia josephiniae is South Africa’s largest geophyte, both in terms of the size of the bulb and the size of the inflorescence. It is also known as the Candelabra Lily or kandelaarblom or lantanter in Afrikaans. The vast inflorescences are produced in autumn after the first rains have arrived and are pollinated by sunbirds. Once seed has been set the leaves emerge during the winter months. The plant becomes dormant during summer. This makes it highly resilient to low winter temperatures and even fire.

Brunsvigia josephiniae is found in renosterveld vegetation on Malmesbury shale, limestone and sandstone derived soils from the western Karoo, Worcester, Malgas and eastwards to Willowmore. Populations of this species have become increasingly fragmented as a result of habitat transformation for agriculture. This species is further threatened by collection of bulbs from the wild for medicinal use. It is therefore Vulnerable on the Red List of South African Plants.

Brunsvigia bosmaniae

Top & Above: Mass flowering of Brunsvigia bosmaniae at Nieuwoudtville, Bokkeveld Escarpment.

Perhaps one of the most well-known members of the genus, Brunsvigia bosmaniae is known for its spectacular pink autumn displays when it flowers en masse after autumn rain. It is named after a Mrs. J.D. Bosman, who collected the type material of this species.  It is relatively common in the Cape Floristic Region, distributed from southwestern Namibia southwards to Tygerberg in the greater Cape Town area. Brunsvigia bosmaniae grows on flats and lower hill slopes on soils derived from dolerite, shale, limestone and granite.

Brunsvigia elandsmontana

Top & Above: Brunsvigia elandsmontana. 

Brunsvigia elandsmontana is a relatively new species to science, being described by Dee Snijman in 1994. It is dwarf in size and easily identified by its attractive pink flowers. This species grows in Swartland Alluvium Fynbos on well drained pebbly flats and flowers from March to May. Brunsvigia elandsmontana  is a relatively rare species with around 700 individuals present at just one locality. It is listed as Critically Endangered on the Red List of South African Plants.

Brunsvigia marginata

Above: Brunsvigia marginata. 

This spectacular member of the genus is hard to miss with its glittering bright red blooms and purple stamens. Brunsvigia marginata was first collected from the Cape at an unrecorded location and cultivated by horticulturalists Georg Scholl and Franz Boos from Schonbrunn Palace near Vienna during the 18^th Century. It was also introduced to Kew Gardens by Francis Masson in 1795 from bulbs he collected at the Cape.

This species is distributed from Citrusdal in the Cederberg southwards to Paarl and Worcester where it grows in colonies in fynbos on shale derived soils on north and east facing mountain slopes. Flowering takes place from March to June, often in profusion after fire. However, this species is not wholly fire dependent as certain clones flower annually without being burnt.

South Africa’s plant extinction crisis: What can we do?

All life on earth depends on plants. They feed us, they clothe us and more than 40% of our medicines are derived from them. Plants can modify weather systems, count and even communicate with each other. There are currently around 369,000 vascular plant species known to science, with around 2000 new plant species being described each year. However, 21% or 1 in 5 plant species is currently threatened with extinction.

Above: One of the last wild populations of Lachenalia viridiflora (CR) growing on a housing plot for sale in its West Coast home.

A recent study published in the journal Nature, Ecology and Evolution by researchers from Royal Botanic Gardens Kew and Stockholm University found that 571 plant species became extinct over the last 250 years, an extinction rate 500 times higher than would happen without human influence. This crisis if not addressed is something that will have a cascade effect, leading to extinctions of other life forms dependent on those species including animals, birds and pollinating insects.

Top: One of the last populations of Gladiolus jonquilliodorus on the Cape Peninsula. Above: Watsonia humilis (CR) at its last wild home on the Cape Flats, threatened by industrial development, illegal dumping and alien plant invasion.

One of main hotspots for plant extinctions was found to be South Africa’s Western Cape, second only to Hawaii. The Western Cape has lost a total of 37 plant species. However, these are just the plant extinctions that we know about, with the real numbers including lesser known taxa likely far higher.

Above: Haemanthus pumilio (EN), suffering from ongoing habitat loss from transformation for agriculture and wetland drainage.

Far more plant species are also threatened with extinction in the Cape Floristic Region, being pushed towards the brink by habitat loss from urban development, alien plant invasion, transformation for agriculture, overgrazing, water pollution and inappropriate fire regimes.

Top: One of the last Gladiolus aureus (CR) in the wild on the southern Cape Peninsula. Above: Moraea aristata (CR).

One such example is Gladiolus aureus, also known as the Golden Gladiolus. It is Critically Endangered in the wild and likely one of the most threatened species on the Cape Peninsula with less than 10 individuals remaining. Its habitat on the southern Peninsula has become highly degraded due to gravel quarrying and alien plant invasion and material for ex-situ conservation is currently held in only one botanical garden. This beautiful bulb is teetering on the brink. The Critically Endangered Protea odorata is in a similarly perilous state, with only three individuals remaining in the wild and efforts to cultivate it ex-situ having mixed results.

 

Above: Moraea melanops (EN), endemic to Critically Endangered Overberg Renosterveld and threatened by habitat loss from transformation for agriculture, overgrazing and runoff from agricultural chemicals.

So what can we do to turn the rising tide of losses? First we need to know as much as we can about our threatened species. Where do they grow and what habitats do they prefer? Where do they call home? Our partners at the Custodians of Rare and Endangered Wildflowers, supported by dedicated citizen science volunteers. Why not get involved? We also need to build capacity in the conservation sector, training the upcoming botanists and conservationists of the future so that they know, can identify and care about our flora.

Above: Restored population of Serruria furcellata (CR) following numbers of this species being reduced to one wild individual.

Once we know where our imperilled species are found, we need to conserve their home and habitats. We all have the power to lobby against inappropriate developments where we live as well as encouraging our local governments to prioritise clearing alien vegetation, both for conservation and for water security. Consider donating to South Africa’s conservation nonprofits who tirelessly work for our biodiversity. There are many local community groups volunteering for conservation action so why not join them? Every conservation action makes a difference.

After the fire: Bettys Bay fynbos five months on

Text and photos by Zoë Poulsen

On New Year’s Eve of this year, in the small Overstand town of Bettys Bay, a boat flare was set off, landing in the fynbos on the mountains above. This was to be the beginning of one of the biggest fires of the 2019 season and the worst in the Overstrand for more than 30 years.

Above: Fynbos above Harold Porter National Botanical Garden two weeks after the Betty’s Bay fire, looking towards Leopards Kloof.

After several days with fire crews from across the Overberg and beyond giving all their worth at the fire line, it was thought that Bettys Bay and nearby Pringle Bay were out of danger. Then the wind picked up. Howling gale force southeaster winds sent the fire barrelling down the mountainside into the heart of Bettys Bay and Harold Porter Botanical Gardens, jumping across the R44 and roaring through the fynbos towards Pringle Bay. Terrified residents were evacuated, houses were ablaze and a life sadly lost. Many lost everything and the community was left reeling. My heart goes out to all those affected.

Above: Blooms of Amaryllis belladonna near Pringle Bay after the Betty’s Bay fire.

South Africa’s fynbos is a fire prone and fire dependent vegetation, making it a tough neighbour to live alongside when the summer fires come. Without fire there would be no fynbos. Many fynbos species are completely reliant on fire to flower, set seed and reproduce. After this tragedy comes new life to the veld, like a phoenix out of the ashes.

Top: Locally endemic Haemanthus canaliculatus flowering after the Betty’s Bay fire. Above: Fire lily (Cyrtanthus ventricosus) in bloom two weeks after the Betty’s Bay fire.

Initially after a fire moves through the landscape the grey ash and blackened stems of fynbos shrubs resemble a lunar landscape. Across the landscape in the first few days the heat from the fire and chemicals from the smoke trigger the opening of seed cones and release of many thousands of seeds. These will form the next generation of Proteaceae.

Above: Red hot pokers (Kniphofia uvaria) blooming in wetland at Pringle Bay after the Betty’s Bay fire.

Around ten days after the fire, on southwest facing slopes across the area fire lilies emerged, their blooming triggered by heat and chemicals in the smoke from the fire. Cyrtanthus ventricosus are the only true ‘fire lilies’, rarely seen and often waiting for years for an opportunity to bloom.

Above: The zigzag trail above Harold Porter NBG, looking towards Disa Kloof, with fynbos resprouters and residers growing apace.

As the autumn rains come later in the season, they trigger the emergence of autumn bulbs such as Amaryllis belladonna and rare local endemic Haemanthus canaliculatus, flowering en masse after the fire. By April, the wetlands by the junction to Pringle Bay were ablaze with colour from carpets of red hot pokers (Kniphofia uvaria).

Above: King Protea (Protea cynaroides), South Africa’s national flower, resprouting above Harold Porter NBG after the Betty’s Bay fire.

By late May, Harold Porter NBG’s hardworking horticultural team had repaired many of the paths in the garden, granting access to Leopard’s Kloof and the upper contour path through the fynbos leading to Disa Kloof. With some fynbos species re-sprouting and some reseeding after fire moves through the landscape, the once blackened ash-covered slopes are now green, full of new shoots from king proteas (Protea cynaroides) to sundews (Drosera spp.). The tiny delicate white flowers of Crassula capensis, also known as Cape Snowdrops, can be seen blooming in damp areas under rock overhangs.

Above: Sundews (Drosera spp.) and a Restio resprouting after the Betty’s Bay fire.

The hard work to restore Harold Porter NBG fully to its former glory will no doubt continue over the next few months, with much work still to be done. Those affected will never forget the 2019 Bettys Bay fire. Meanwhile as new life comes to the fynbos, visitors to the garden will marvel at the constantly changing new growth emerging from the ashes.

Paintbrushes of the Veld: Spotlight on Haemanthus

Article and photos by Zoë Poulsen

Known for its bizarre paintbrush-like flowers, the genus Haemanthus is one of the most famous of the Amaryllidaceae family. When autumn comes to the veld and little else is in flower, these strange blooms emerge from the dry earth where they have been lying dormant over the summer months. The genus is endemic to Southern Africa and found only in Namibia, South Africa, Lesotho and Swaziland with the main centres of diversity being central and southern Namaqualand and the Knersvlakte around Vanrhynsdorp. Some species are widespread and occur across a wide variety of different habitats whereas others are specialists adapted to a specific habitat niche. Some Haemanthus from winter rainfall areas flower in profusion after fire has cleared overstorey vegetation. Most members of the genus grow in colonies, a phenomenon perpetuated by the peduncles leaning towards the ground under the weight of the seeds as they ripen leading to germination around the parent plant.

Above: Haemanthus albiflos growing in afrotemperate forest habitat on the Garden Route.

Haemanthus albiflos is one of only three evergreen species of Haemanthus. It was first described and illustrated by N.J. Jacquin in 1797 from material collected from the Cape. This species is distributed from Stilbaai eastwards to northern KwaZulu Natal where it grows in coastal and riverine forest, thornveld and valley bushveld in light to deep shade. Flowering takes place from May to October.

Top & Above: Haemanthus coccineus in flower and fruit on the Bokkeveld Escarpment.

Haemanthus coccineus is the most widely distributed members of the species. It is found from southern Namibia southwards to the Cape Peninsula, eastwards to the southern Eastern Cape and inland to Sutherland and Ladismith. This species is found in habitat as varied as its distribution, growing on soils derived from sandstone, granite, quartzite, shale and limestone. Haemanthus coccineus is often found in rocky habitats where it commonly grows in the shade of boulders. In contrast it is also found growing on coastal dunes. Flowering occurs from February to April.

Above: Haemanthus barkerae flowering in habitat.

My first encounter with the intense pink inflorescences of Haemanthus barkerae was a lonely flowerhead lying on the ground after having likely been removed by foraging baboons. This species is endemic to South Africa’s Northern Cape, distributed from Louriesfontein to the Hantamsberg and northern Tanqua Karoo where it grows on heavy clay soil. Haemanthus barkerae was only recently described, previously being thought to be part of Haemanthus pumilio until it was revised by Dee Snijman in 1984. Flowering takes place from March to April.

Above: Haemanthus canaliculatus flowering after fire in Hangklip Sand Fynbos.

Haemanthus canaliculatus is another range restricted member of the genus, known only from the Overstrand coast between Rooiels and Betty’s Bay. It was first collected in Betty’s Bay by a Mrs. M Brunt in 1943, but not described until 1966 by botanist Margaret Levyns in the Journal of South African Botany. The species epithet of Haemanthus canaliculatus refers to the deeply channelled leaves that typify this species. It is a wetland specialist, growing in peat in Hangklip Sand Fynbos. It flowers in profusion after fire, growing in dense colonies. Haemanthus canaliculatus is Endangered on the Red List of South African Plants as a result of housing development reducing the number of populations.

Above: Endangered Haemanthus pumilio flowering in habitat.

Last but not least is the diminutive Haemanthus pumilio, its species epithet meaning ‘dwarf’ in reference to its low growing habit. This species was first described in 1797 by N.J Jacquin having been introduced to RBG Kew by Francis Masson who collected it at an unrecorded locality at the Cape. Haemanthus pumilio is endemic to the lowlands around Stellenbosch and Paarl where it grows on gravelly clay flats in renosterveld vegetation. Much of its habitat has been lost as a result of urbanisation and transformation for agriculture and it is now only known from a handful of sites. Flowering takes place from March to April and the seeds are thought to be water dispersed. Haemanthus pumilio is listed as Endangered on the Red List of South African Plants.