Cape honey flower
Botanical name
Melianthus major
Family
Melianthaceae (honey flower)
Also known as
False castor oil plant
Where is it originally from?
South Africa
What does it look like?
Smelly, clump-forming shrub (<2+ m), with stout, rough, soft-wooded, hollow stems and suckering root system. Frond-like leaves (50-100 cm long), are covered in grey, hairy down especially underneath, are divided into 11-21 distinctively folded leaflets (8-15 cm long) and are deeply serrated with 1 cm teeth along edges. Tall, erect flower stalk (40-80 cm) has foul smelling, dark reddish-brown flowers (2 cm long, Jul-Apr) which produce large amounts of nectar, are followed by inflated, papery, sharply-angled seed capsules (2-5 cm long) containing long, shiny black seeds (5-6 mm long).
Why is it weedy?
Seed are long-lived and it forms dense, spreading stands via suckering roots. Grows in well drained soils of any quality, tolerates wind, salt, hot and cold temperatures, and damp or drought conditions and is partly shade-tolerant. Poisonous (not grazed).
How does it spread?
Seed capsules are water-borne (sea or fresh) and to a lesser extent, wind-borne. Suckering roots are spread in dumped vegetation. Common sources are gardens, waste places, and tips.
What damage does it do?
Smothers low-growing coastal species, forming large stands and destroying habitats, often leading to subsequent invasion by weedy vines. Native birds may be affected by nectar.
Which habitats is it likely to invade?
Sand dunes, sheltered coastal and steep areas, estuaries, inshore islands, disturbed lowland forest margins, shrubland, and fernland, especially on the east coast
What can I do to get rid of it?
1. Physical removal - Hand pull small plants, or dig out entire plant including roots and mulch (all year round)
2. Cut and paste (all year round) - Cut the stem/trunk as close to the ground as possible and cover the entire stump with herbicide as soon as possible after cutting. Apply metsulfuron gel (10g/l strength). When a gel is inadequate apply a solution of diesel and product containing triclopyr + picloram (20:1 diesel:triclopyr/picloram). Apply the mixture over the entire exposed surface of the cut stump, i.e. top and sides.
3. Foliar spray - Apply herbicide using a hand held sprayer/knapsack to plants <1m tall or gun and hose for larger infestations. Apply metsulfuron herbicide (600g/kg active ingredient at 5g/10L knapsack or 20g/100L gun and hose) plus organosilicone penetrant (3ml/L) Note: Metsulfuron overspray will kill other (desirable) broadleaf plants and has residual activity in the soil which aids in killing below ground parts OR apply picloram/triclopyr herbicide (picloram 100g/l and triclopyr 300g/l active ingredient at 6ml/L) plus organosilicone penetrant (1ml/L) to thoroughly wet all parts of plant. Note: Triclopyr and picloram herbicides are ‘grass friendly’ but overspray will kill other (desirable) broadleaf plants. Picloram has residual activity in the soil which may leach and kill other plants. Do not use under and around other (desirable) broadleaf plants.
CAUTION: When using any herbicide or pesticide, PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and directions for the purchase, use and storage of the product, are followed and adhered to.
What can I do to stop it coming back?
Roots resprout profusely. Livestock won’t eat it because of taste and poison, however they will eat wilting leaves. Plant invades grazed sites, therefore exclude livestock at all times, especially when controlling weed. Cut stems may be left on site to rot down, however followup on root regrowth will be needed.
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