Alternative common names:
Rooisonneblom (Afrikaans), giant Mexican sunflower, Japanese sunflower, Mexican sunflower, shrub sunflower, tree marigold.
Indigenous to Mexico, the red sunflower is a large, erect and robust annual that grows up to 3m in height. It was introduced to South Africa during the early 1900s as an ornamental plant. Its abundance in South Africa has been escalating over the past 12 years in conservation, agricultural, urban and rural areas, particularly near waterways, disturbed sunny areas and along railways and roadsides.
Where does this species come from?Eastern Mexico and Central America.
What is its invasive status in South Africa?NEMBA Category 1b.
Where in South Africa is it a problem?Gauteng, North West, Mpumalanga and Limpopo.
How does it spread?The seeds are dispersed by animals, water and on clothing, They may also be spread in dumped garden waste and contaminated agricultural produce.
Why is it a problem?
It competes with indigenous species and obstructs access to riverbanks. Dense stands along road verges can obstruct motorists' vision.
What does it look like?
Leaves: Alternate, dark green, rough, hairy, up to 150mm long and 100mm wide, triangular-ovate, sometimes deeply three-lobed, petioles winged.
Flowers: Bright orange-red, large and showy, up to 90mm across. Solitary on long stalks, much swollen and velvety below the heads, terminating the main and side branches. The buds are pointed and the bracts below the petals are narrow and pointed.
Fruit/seeds: Brown achenes in a rounded, spiky mass.
Does the plant have any uses?
Ornamental and a source of honey.