Wild ginger

Common name:  Wild ginger 
Scientific name:   Hedychium gardnerianum
Management programme:  Organism of interest

Report this pest!

If you have seen or suspect the presence of this pest we need to know. Please report it.

Contact Otago Regional Council on 0800 474 082 or biosecurity@orc.govt.nz

Why is it a pest?

Wild ginger is an invasive plant that is long-lived, fast growing and able to outcompete native plants. It forms deep rhizome (underground fleshy stem) beds that replace all other species. Nothing can grow up through the mats of tubers, and the dense leaves block light and smother natives. 

Seeds are spread by birds and pests, and rhizomes will resprout from any fragment and can survive being crushed, immersed in the sea, and away from soil for years.  

Wild ginger can grow in a variety of habitats. It is extremely shade tolerant, tolerates most soil types — good or poor drainage and fertility — and is drought and frost tolerant once established.  

What does it look like?

  • Size: Non-woody perennial that grows up to 2 metres. It is ginger scented with erect, unbranched stems that thicken to a short pinkish 'collar' at the base. 
  • Leaves: Shiny, slightly ‘hanging’ leaves that alternate on stems.  
  • Flowers/seeds: Flowerheads are usually 25-45 cm tall with many fragrant lemon-yellow flowers. Clearly visible red stamens are produced from January to March and develop into fruiting spikes with fleshy orange fruits (1.5–2 cm long) containing many bright scarlet seeds. 
  • Root system: Massive, taro-like rhizomes that are long and shallow rooted, have many branches, form deep beds and grow over each other close to the surface. Each rhizome segment (4 x 10 cm) usually produces an above-ground stem annually. 
  • Habitat: Includes damp forests and forest margins, streamsides, river systems, shrublands, and fernlands.  

When can I spot it best?

Wild ginger can be easily identified by its clearly visible red stamens, produced in summer and early autumn (January–March). 

What are the rules?

There are no rules for landowners in Otago regarding wild ginger. Under Otago’s pest plan, it is only classified as an organism of interest, with sites being recorded for possible opportunities in the future.

Landowners/occupiers are encouraged to report wild ginger on their properties or sightings using the reporting tool at orc.govt.nz/reportpests 

What should I do?

Physical control: 

Dig out small patches (all year round) and dispose of at landfill, burn, or bury deep. Make sure to dig out the rhizomes. 

Chemical control: 

  • Cut the stump near the ground and paste using a suitable herbicide gel containing either picloram, glyphosate, or metsulfuron. Leave stems and leaves on site to rot down. 
  • Spray foliage in spring to late autumn using the herbicides mentioned above. A penetrant will need to be added in winter. 
  • Cut the vines at a convenient height in winter and spray the regrowth in the spring. 
  • For dense patches, keep spray away from roots of vulnerable plants.  
  • Don't replant sprayed sites for six months. 

Caution: When using any herbicide or pesticide, PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and safety requirements are followed. 

Disclaimer: Mention of product trade names does not endorse these products nor imply criticism of similar products not mentioned. The Otago Regional Council does not give any warranty that the information is accurate or complete or that it is suitable for all circumstances. 

When using any herbicide or pesticide PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and safety requirements are followed. 

Disclaimer: Mention of product trade names does not endorse these products nor imply criticism of similar products not mentioned. The Otago Regional Council does not give any warranty that the information is accurate or complete or that it is suitable for all circumstances. 

Management programme