Mexican Sunflower – Category 1 Invasive Plant
You may have noticed tall, yellow blooms brightening up the roadsides this autumn. But don’t be fooled—those striking flowers belong to the Mexican sunflower (Tithonia diversifolia), one of South Africa’s most aggressive Category 1 invasive species.
Growing up to 3 metres tall, these eye-catching plants produce a spikey round seed head that bursts with thousands of lightweight seeds, easily carried by wind, water, and animals. Once established, they form dense colonies that smother indigenous vegetation and transform natural habitats, posing a serious threat to our local biodiversity.
What makes them so invasive?
This shrub thrives in heat and drought, grows rapidly, and spreads with alarming ease—making it a nightmare to control if left unchecked.
How to remove it:
- Small plants can be hand-pulled or sprayed with an approved herbicide.
- Larger plants should be cut at the base and the stump painted immediately with a suitable herbicide.
Watch for regrowth and treat promptly with follow-up spraying.
💡 Did you know?
Many garden plants that seem attractive and harmless are, in fact, classified as illegal invaders. By replacing invasive species with indigenous plants, you can enjoy a beautiful garden that supports local ecosystems and wildlife.
Need help identifying or removing alien invasive plants from your property?
Contact the Bazley Conservancy – we’re here to assist.
Bazley Conservancy contacts:
Liz Forsdick: 082 701 3402
Pete Harvey: 072 200 8126
