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Portulacaria afra (Elephant Food) - An upright growing plant that can reach to 8 to 12 feet tall but often seen about half or less this height with reddish brown stems and 1/2 inch long emerald green succulent leaves. In dry years it can produce showy tiny pale lavender flowers held near the branch tips in summer months, but up until recently this plant was rarely seen in bloom as it needed drier conditions than Southern California usually has had to reliably produce flowers, but in drier winters years experienced with our global climate change, this plant seems to be blooming more often where plants are not irrigated.
Plant in sun or shade with little or no supplemental irrigation. Hardy to at least 25° F – undamaged after 3 nights to this temperature in 2007 and plants survived with some stem damage in the cold Christmas 1990 freeze with temperatures in our garden below 20° F. Makes a great drought tolerant foundation plant and can be kept almost any size with pruning.
Portulacaria afra is native to South Africa where it grows in warm sites on rocky slopes with other succulents in the eastern parts of South Africa from the Eastern Cape northwards into KwaZulu-Natal, Swaziland, Mpumalanga and the Limpopo Province and further north into Mozambique. The genus name is a combination of Portulaca (a genus name) and 'arius' meaning "pertaining to" in reference to the similarity of plants in this genus to those in the genus Portulaca which itself comes from the Latin word 'portula' meaning "a small door" in reference to the fruits which open with a small lid. The Portulacaria have long been considered to be in the Portulaca family, the Portulacaceae, but more recent molecular phylogenetic studies have indicated that Portulacaria should rightfully be placed in the Didiereaceae, which was otherwise entirely found in Madagascar. The specific epithet is in reference to the plants coming from Africa.
Though usually commonly called Elephant Food, another common English name is Porkbush and the Afrikaans name is Spekboom, which translates from two words, 'spek' meaning "bacon" and 'boom' meaning "tree" as Bacon Tree. These names come from the fact that the leaves are edible, though with a sour flavor. It is widely browsed by wild and domestic animals in Africa and while it is touted as a favorite food of elephants, ostriches, cattle and humans can eat it, though it seems to be less palatable to deer and rabbits in our California gardens – go figure. Occasionally this plant is also called "Dwarf Jade", a name that we think is confusing since this plant is not that closely related to the Jade plant, Crassula ovata.
Portulacaria afra has also been used to bind soil to prevent erosion and is noted as a very efficient plant for absorbing atmospheric carbon (CO2) and is described as a "carbon sponge", using both the more common C-3 pathway for carbon fixation in the photosynthesis process and, when the temperatures rise, also using the Crassulacean Acid Metabolism (CAM) pathway that is found in many other succulents. Because of this use of the two photosynthesis carbon pathways, this plant has garnered some amount of attention in South Africa's social media with a byline "The Spekboom Challenge", which encourages people to plant it as a natural carbon sequestration method to combat the country's carbon emissions. While this plant is pretty amazing for its ability to switch carbon pathways and sequester carbon in it dry natural environment, there is more carbon emitted into the atmosphere in South Africa than could be offset by restoring the original range of Portulacaria afra (more than 4 million acres) and the science also does not support the wholesale mass planting of it elsewhere, particularly if replacing plants in other biomes with solid stands of Portulacaria afra as a strategy to combat rising atmospheric carbon levels.
Besides this species plant we also grow the following cultivars: Portulacaria afra forma macrophylla - a large leafed form, Portulacaria afra 'Skyscraper' - a narrow upright form, Portulacaria afra 'Cork Bark' - a corky bark form great for bonsai use, Portulacaria afra 'Low Form' - a prostrate form green leaves, Portulacaria afra 'Aurea' - a large plant with yellow new growth, Portulacaria afra 'Variegata' - an upright plant with white variegated leaves and Portulacaria afra 'Medio-picta' - a stunning low growing plant with pink stems and leaves that have a wide central cream stripe. All are great drought tolerant plants useful in the landscape or as container specimens. We have sold this plant since 1989.
The information about Portulacaria afra displayed on this web page is based on our research conducted in the nursery's horticultural library and from reliable online resources. We also include observations made about it as it grows in our nursery gardens and other gardens we have visited, as well how the crops have performed in containers in our nursery field. We will also incorporate comments we receive from others and welcome hearing from anyone with additional information, particularly if they can share cultural information that would aid others in growing this plant. |
