The genus Encephalartos

Encephalartos Lehm. is the great African cycad genus — approximately 68 species, all endemic to the African continent, ranging from Nigeria and Sudan to the Cape of South Africa. It includes the most sought-after, most expensive and most illegally traded cycads on Earth. A mature specimen of a rare Encephalartos species can command tens of thousands of euros on the black market — a price that has driven poaching to crisis levels in South Africa and made Encephalartos a focal point of global plant conservation efforts.

For gardeners, the genus offers an extraordinary range of ornamental forms: compact, blue-leaved jewels (Encephalartos horridus, Encephalartos lehmannii), massive landscape specimens (Encephalartos transvenosus, Encephalartos altensteinii), and everything in between. Several species are surprisingly cold-tolerant, surviving USDA zone 9a or even 8b in well-drained conditions.

Taxonomy and systematic position

Family Zamiaceae, order Cycadales. The genus was described by Lehmann in 1834. The name comes from the Greek en (in), kephalē (head) and artos (bread) — a reference to the starchy pith of the stem, which was historically processed into a bread-like food by indigenous peoples. The most comprehensive modern taxonomic treatments are those of Dyer (1965), Goode (1989, 2001) and Vorster (2004). The World List of Cycads recognises approximately 68 species.

Geographic range and diversity

Genus Encephalartos is exclusively African. The centre of diversity is southern Africa, particularly South Africa (which harbours approximately 37 species — over half the genus), Mozambique (approximately 8 species), and the eastern highlands of Zimbabwe and Malawi. A few species extend into tropical East Africa (Tanzania, Kenya, Uganda), Central Africa (the Congo Basin — Encephalartos ituriensis, Encephalartos laurentianus), and West Africa (Nigeria — Encephalartos barteri). One species (Encephalartos hildebrandtii) reaches the Kenya/Somalia coast.

Ecological diversity

Habitats range from coastal dune scrub and sand forest (Encephalartos ferox) to montane grasslands above 2,000 m (Encephalartos cycadifolius, Encephalartos ghellinckii), fire-prone savanna (Encephalartos natalensis, Encephalartos altensteinii), subtropical thicket (Encephalartos longifolius), arid Karoo scrub (Encephalartos lehmannii) and tropical lowland forest (Encephalartos hildebrandtii). This ecological range is reflected in the widely varying cultivation requirements across the genus.

Conservation and threats

The most poached plants on Earth

Encephalartos is arguably the most conservation-critical cycad genus. Multiple species are known from fewer than 100 wild individuals. Encephalartos woodii is extinct in the wild — only a single male plant was ever found (in 1895 in KwaZulu-Natal), and all cultivated specimens are clones of that individual. No female Encephalartos woodii has ever been found. Encephalartos latifrons, Encephalartos hirsutus, Encephalartos middelburgensis, Encephalartos dolomiticus and Encephalartos cupidus are all critically endangered with tiny wild populations.

Poaching of wild plants for the private collector market, primarily in South Africa, is a persistent and escalating problem. South African authorities have prosecuted high-profile cases, but enforcement is difficult in remote habitats. The 2024–2025 IUCN Cycad Specialist Group report highlights the ongoing severity of this threat.

CITES

All Encephalartos species are listed under CITES Appendix I — the highest level of protection. This means that international commercial trade in wild specimens is completely prohibited, and trade in artificially propagated specimens requires permits from both exporting and importing countries. This is a stricter listing than for any other cycad genus (most others are Appendix II). Gardeners and collectors must ensure that any Encephalartos they acquire is accompanied by legitimate CITES documentation.

Extinct in the Wild — six species, six failures

Six Encephalartos species are classified as Extinct in the Wild (EW) or functionally extinct — the highest count for any plant genus on Earth. Each represents a different mode of loss:

Encephalartos woodii — Ngoye Forest, KwaZulu-Natal. A single male individual was found in 1895; no female has ever been discovered. All cultivated plants are clones. No possibility of sexual reproduction within the species (backcross programmes with E. natalensis are underway).

Encephalartos heenanii — Barberton, Mpumalanga / Eswatini. Population crashed from 272 stems (1996) to 45 (2006) to zero (2019). Both sexes exist in cultivation but the species is notoriously difficult to grow, “often dying for no apparent reason.”

Encephalartos relictus — Eswatini. Known from a single male plant found in 1971 by J.J.P. du Preez. Never found again. Only male clones exist; no backcross programme has been attempted. Evolutionarily extinct.

Encephalartos brevifoliolatus — Drakensberg escarpment, Limpopo. Five male plants found in 1990; all subsequently lost from the wild. Only one female cone has ever been produced in cultivation. Fraud risk: E. laevifolius is frequently sold as brevifoliolatus.

Encephalartos nubimontanus — Wolkberg, Limpopo. Population declined from 66 counted plants (1990s) to zero (2004). The exception among the EW species: both sexes survive in cultivation, seed is produced, and the species is the fastest-growing blue Encephalartos. It has the clearest path to reintroduction.

Encephalartos chimanimaniensis — Chimanimani Mountains, Zimbabwe. Known from a single river catchment; recent field surveys found no surviving plants. Not yet formally reclassified as EW by the IUCN, but Africa Cycads and PACSOA consider it extinct. If confirmed, it would be the first Encephalartos lost from outside South Africa.

A seventh species, Encephalartos dolomiticus, is classified as Critically Endangered (Possibly Extinct in the Wild) — only 4 plants were located in a 2019 survey, and unconfirmed reports suggest these too may have been taken. The line between CR and EW is, for dolomiticus, a matter of whether anyone has checked the Wolkberg dolomite ridges since 2019.

Cultivation

Light

Most Encephalartos species require full sun for optimal growth and cone production. Species from forest margins or shaded habitats (Encephalartos villosus, Encephalartos ferox) tolerate partial shade, but open, bright conditions are preferred for the majority. Strong light promotes compact, well-armed leaves and better cold hardiness.

Temperature and cold hardiness

Cold tolerance varies significantly across the genus, roughly correlating with altitude and latitude of origin:

  • Hardy (−5 to −8 °C, USDA zone 8b–9a): Encephalartos friderici-guilielmi (montane grasslands of the Eastern Cape, 1,500–2,000 m — the hardiest species, surviving snow cover), Encephalartos cycadifolius, Encephalartos ghellinckii, Encephalartos lehmannii, Encephalartos horridus.
  • Semi-hardy (−2 to −5 °C, USDA zone 9a–9b): Encephalartos altensteinii, Encephalartos longifolius, Encephalartos natalensis, Encephalartos princeps, Encephalartos trispinosus.
  • Tender (0 to −2 °C, USDA zone 10): Encephalartos ferox, Encephalartos hildebrandtii, Encephalartos gratus, Encephalartos kisambo and most tropical species.

As always, dry winter soil dramatically improves cold tolerance. The montane species of the Eastern Cape (Encephalartos friderici-guilielmi, Encephalartos cycadifolius) experience regular frost and snow in the wild and can be grown outdoors in favourable USDA zone 8b–9a microclimates in Mediterranean Europe, provided drainage is impeccable.

Substrate

Excellent drainage is essential for all species. In-ground: amend heavy soil with coarse pumice, volcanic gravel and coarse sand, or plant on raised mounds. In pots: use a primarily mineral mix (60–70% pumice/perlite/coarse sand, 30–40% composted bark or coco coir). Avoid moisture-retentive media. Many Encephalartos species grow naturally on rocky, well-drained slopes or in sandy soils. Soil pH is generally not critical; slightly acidic to neutral is ideal for most species.

Watering

Water thoroughly during the growing season (spring–autumn), allowing the substrate to dry between irrigations. Reduce substantially in winter. Species from arid habitats (Encephalartos lehmannii, Encephalartos horridus) need minimal water even in summer. Tropical species (Encephalartos hildebrandtii) tolerate more moisture but still require drainage. Less water is better.

Propagation

Pollination

Dioecious. Hand pollination is the standard method in cultivation. Encephalartos pollination in the wild typically involves specialised beetles (Curculionidae, Erotylidae) attracted by thermogenesis and volatile chemicals from the male cone. In cultivation, collect pollen by shaking mature microsporophylls over paper, then apply directly to the ovulate cone’s receptive surfaces using a brush or puffer. Pollen can be stored frozen (−18 °C) for up to a year.

Seed maturation and preparation

Seeds mature 12–18 months after pollination. Mature seeds are large (3–5 cm), typically bright red, orange or yellow (sarcotesta colour varies by species). Remove the sarcotesta completely (wear gloves — it is irritating and toxic). Soak cleaned seeds in warm water for 24–48 hours. Fresh seed gives the best germination; viability declines over months.

Sowing

Bury seeds halfway in a coarse, well-drained medium (pumice, perlite, coarse river sand). Cover with clear plastic. Maintain 25–30 °C. No light required during germination. Most Encephalartos species germinate in 4–12 weeks. Some species have long after-ripening requirements — respect these or seeds may rot (as noted by experienced growers on the Agaveville cycad forum). After the primary root emerges, pot in a deep, narrow container with a mineral-dominant mix.

Raising seedlings

Growth is very slow — 1–2 leaf flushes per year. Provide bright light (full sun for most species from an early age), warmth, and careful watering. Seedlings are vulnerable to rot, slugs and scale insects. Feed sparingly with slow-release fertiliser. Most species produce a recognisable caudex after 3–5 years.

Vegetative propagation

Many Encephalartos species produce basal suckers that can be removed and rooted. Allow suckers to develop several leaves before detachment. Let the wound dry for a week before potting in a well-drained medium. Some species (Encephalartos villosus, Encephalartos natalensis) sucker prolifically; others (Encephalartos woodii, Encephalartos horridus) rarely or never do.

Pests and diseases

Cycad aulacaspis scale (Aulacaspis yasumatsui) — less devastating for Encephalartos than for Cycas, but increasingly reported on African species. Monitor and treat with systemic insecticide if detected.

Mealybugs — common on container-grown plants, particularly at the base of leaf stalks and between cone scales. Treat with isopropyl alcohol, horticultural oil or systemic insecticide.

Scale insects (various species) — occasional on leaves and trunks. Treat with horticultural oil.

Root rot — Phytophthora and Fusarium in waterlogged soil. Prevention: drainage. Fatal if the caudex is affected.

Stem rot (soft rot) — bacterial or fungal infection of the caudex, often following mechanical damage, overwatering or transplant stress. Cut away affected tissue to clean, firm material, treat with fungicide and allow to dry thoroughly before replanting. A dry, warm recovery period is critical.

Species of Encephalartos

Approximately 68 species, all endemic to Africa. Arranged here by broad geographic region, from south to north.

Southern Africa — Eastern Cape and KwaZulu-Natal

Southern Africa — Limpopo, Mpumalanga, North West

Southern Africa — Eswatini, coastal Mozambique, and sand forest

Zimbabwe–Mozambique highlands — the manikensis complex

Northern and central Mozambique, Malawi

Tropical East and Central Africa

West Africa

Authority websites and online databases

Encephalartos.org — Palm and Cycad Societies of Australia (PACSOA)
Detailed species profiles, photographs and cultivation notes for all Encephalartos species.
https://www.pacsoa.org.au/wiki/Encephalartos

World List of Cycads
https://www.cycadlist.org/

IUCN SSC Cycad Specialist Group
https://www.cycadgroup.org/

The IUCN Red List of Threatened Species
https://www.iucnredlist.org/

Plants of the World Online (POWO)
https://powo.science.kew.org/

CITES Species+ Database
https://speciesplus.net/

SANBI (South African National Biodiversity Institute)
Conservation and biodiversity data for South African Encephalartos.
https://www.sanbi.org/

Bibliography

Goode, D. — Cycads of Africa. Volumes 1 and 2. D.P. Goode, 2001. The most comprehensive reference on African cycads. Indispensable for Encephalartos.

Grobbelaar, N. — Cycads: with special reference to the southern African species. Published by the author, 2004. Excellent for cultivation and field data on southern African Encephalartos.

Jones, D.L. — Cycads of the World. 2nd edition, 2002.

Whitelock, L.M. — The Cycads. Timber Press, 2002.

Donaldson, J.S. (ed.) — Cycads: Status Survey and Conservation Action Plan. IUCN, 2003.

Vorster, P. — various taxonomic publications on Encephalartos, including species descriptions and nomenclatural revisions. Published primarily in Bothalia and Encephalartos (journal of the Cycad Society of South Africa).

Cousins, S.R. & Witkowski, E.T.F. — “African cycad ecology, ethnobotany and conservation: a synthesis.” Botanical Review 83 (2017): 152–194.

IUCN SSC Cycad Specialist Group — Annual reports (2016–2025) and Handbook of Cycad Cultivation and Landscaping, 2nd edition. Available at https://www.cycadgroup.org/.