Know Your Weeds: Thunbergia Vine

WHAT IS IT? 

Thunbergia vine, commonly known as blue thunbergia, is a fast-growing vine native to tropical regions like India.

It was introduced into gardens for its striking trumpet-shaped flowers but has become highly invasive in many areas of the Wet Tropics.

WHY IS IT A PROBLEM?

Thunbergia poses a significant threat to environmental areas as well as domestic gardens. It smothers vegetation and trees by climbing and forming dense vine towers. This can lead to the collapse of mature trees and infrastructure due to its weight.

CHARACTERISTICS 

Thunbergia vine is a vigorous climber with heart-shaped leaves and lavender-blue flowers with pale yellow throats. It thrives in tropical and subtropical climates, often found along riverbanks, and in forests, urban bushland and disturbed areas. The vine spreads through tuberous roots and stem fragments.

HOW TO SPOT IT ON YOUR PROPERTY 

Look for robust vines with clusters of conspicuous blue trumpet-shaped flowers and large, tuberous roots. The leaves are bright green, rough-textured, and vary in shape from heart-shaped to angular, like a Choko leaf. The vine often climbs
fences, trees, and other structures in urban infestations.

WHAT TO DO ABOUT IT 

• Prevention: Avoid planting thunbergia in gardens and report infestations to local authorities. Dispose of garden waste appropriately.
• Physical removal: Dig out small plants and tubers. Ensure all fragments are disposed of securely to prevent regrowth.
• Chemical control: Herbicides can be elective. No herbicide is currently registered for control of blue thunbergia in Queensland. However, an off-label use permit (Permit No. PER11463 https://permits.apvma.gov.au/per11463.pdf ) allows use of various herbicides for control of environmental weeds in nonagricultural areas, bushland, forests, wetlands, and coastal and adjacent areas. Follow up control may be required.