Acokanthera oppositifolia

Aug 25, 2018 | Bird Friendly, Butterfly & Moth Friendly, Cold Hardy, Evergreen, Large shrub or small tree, Sun to Partial Shade, Water-wise

Acokanthera oppositifolia, Bushman’s Poison, is typically a large evergreen shrub or small tree that grows beneath larger trees.
    Acokanthera oppositifolia is a large, evergreen shrub or small tree that has dark green leaves. In early spring, it gets lovely clusters of white and pink, fragrant flowers that are followed by attractive purple to black berries. Although poisonous, it is certainly a worthy garden subject.

Family:                       APOCYNACEAE        (Amatungulu family).

Name Derivation:

  • Acokanthera – from Greek ‘akis’, spike or ‘acoce’, pointed, and ‘anthera’ anther giving ‘a sharp or pointed anther’.
  • oppositifolia – ‘opposite leaves’ referring to the leaf arrangement on the stems.

Common Names:          Bushman’s poison-bush (Eng), boesmansgif (Afr), mothoko-nyepe (Nso) inhlungunyembe (Swa & Zul), serokolo (Tsw), mutsilili (Ven), and intlungunyembe (Xho).

FSA Number:                   639                    Zim Number:            838                                  

The densely clustered flowers of Acokanthera oppisitifolia, Bushman’s Poisonbush, are tubular, pinkish outside with white petal lobes.

Form:  

  • An evergreen, multi-stemmed shrub or small tree.
  • Stem is fluted and twisted.

Size:                                   2 – 5 m (–7 m) by 3 – 5 m.

Flowers:

  • The flowers are tubular (+/-1cm), pinkish outside with white petal lobes (.5 cm diameter).
  • The flowers are densely clustered in the leaf axils.
  • Trees in flower may be very showy.

Colour:                              White tinged with pink.

Flowering Months:        Jun – Oct.

Fragrance:                       Sweetly scented.

Foliage:

  • Evergreen.
  • Leaves are simple, elliptic or obovate, 4 – 14 x 2 – 7 cm tapering to a sharp, spine-like tip.
  • Margin is entire, rolled under.
  • Leaves are smooth and leathery, mid to dark green, purple or reddish when young.
  • Lateral veins often raised on both surfaces, reaching almost to the margin.

Thorns:                          No thorns.

Fruit:

  • The fruit is an ovoid drupe (1-2cm).
  • Green, ripening pink-red to purplish-black.

Bark:                     Dark brown bark, on old stems it is deeply fissured.

In the Garden:

  • Its dark green leaves, scented flowers and attractive fruit make for a good garden subject.
  • A good understorey fill plant as well as a screen.
  • A good plant for a wildlife friendly garden, birds eat the fruit.
  • Can be planted close to walls and paving.
  • A water-wise choice.
  • May be pruned to retain it as a shrub.
  • Bushman’s Poisonbush makes a very good container plant.
  • Not a particularly fast growing shrub, up to 50 cm a year.

 Soil Needs:                         Grows well in humus rich soils.

Acokanthera oppositifolia has simple leave, oppositely arranged. The leaves taper to sharp, spine-like tip.
The fruit of Acokanthera oppositifolia start off green, but ripen to maroon, then purple and are almost black when fully ripe.
The fruits are very decorative and rival most exotics that are grown for their attractive fruits.
Care:
  • A low maintenance plant.
  • Prune it to shape.
 Cold Hardiness:                   Cold hardy. Water Requirements:
  • Very drought hardy.
  • Water-wise.
Light Requirements:           Partial shade to full sun.
Roots:              The roots are not aggressive.  Birds:
  • The ripe fruit is eaten by birds.
Insects and Butterflies:
  • Not known to host any butterfly larva.
  • Flowers feed many insects and adult butterflies with nectar.
Medicinal:
  • Dried leaves or roots are used in traditional medicine to treat headaches and snake bites.
  • Weak infusions made from leaves used to treat abdominal pain.
  • Plant is also used to treat tapeworm, anthrax, toothache and colds.
Poisonous:
  • Poisonous.
  • Sap contains a toxic cardiac glycoside, acovenside.
   
The ripe fruit are reportedly not poisonous, and are eaten by birds. They taste terrible and even if they were poisonous, it is highly unlikely anybody would ever eat them.

The bark on old Acokanthera oppositifolia plants is dark brown and deeply fissured.

Notes of interest:
  • The sap of all parts of this plant, except possibly the ripe fruit, is toxic.
  • Extracts of Acokanthera species are used as a component for arrow poison.
  • Although very poisonous, it tastes awful and one’s immediate reaction is to spit it out.
  • It is perfectly safe to touch and does not produce any allergic reactions.
Natural Distribution:
  • Found in WC, EC, KZN, Swa, G, NWP, M, L, Moz and central Zim.
  • Its range extends northwards into East Africa.
 Natural Habitat:
  • Grasslands, thickets, forest, savanna-woodland and savanna-bushveld.
  • Found under or with other trees on rocky outcrops, forest, riverine and coastal bush.

© Malcolm Dee Hepplewhite & Witkoppen Wildflower Nursery, (Text and Photographs) 2012 & 2018.