Agapanthus

Agapanthus

Scientific name
Agapanthus praecox
Family
Agapanthaceae

What does it look like?

Agapanthus grows in clumps with arching, strap-like green leaves with a watery sap. It has thick, long, white rhizomes (roots), and produces purplish-blue or white flowers on top of tall stalks during summer. The seeds are held within a 3-sided capsule that is about 5cm long.

Agapanthus flourishes in coastal, frost-free (or lightly frosted), temperate climates and is commonly cultivated in public and private gardens. It grows wild in urban areas, on roadsides, coastal cliffs, stream edges and forest margins.

Why is it a problem?

Agapanthus tolerates a wide range of soil types and growing conditions, forming dense monocultures that exclude native plants and modify plant communities.

Strong, fleshy roots spread underground to create large clumps and it can also re-grow from root fragments. Plants mature quickly, producing large numbers of seeds (up to 4,000 per flower head) that germinate readily.

Control methods

Banning Agapanthus praecox from sale and distribution does not include sterile varieties.

Physical control

Removal of the bulb-like base of the plant by hand is effective. A trowel or spade may be required for deeper bulbs or larger infestations.

Herbicide control

  • Cut and stump treat with a gel containing either the active ingredient picloram (e.g. Vigilant) or metsulfuron-methyl (e.g. Metgel).
    OR 
  • Spray with 60ml triclopyr (300g/L e.g. Grazon) +10ml penetrant per 10L water
    OR
  • Spray with 200ml Dicamba (100g/L e.g. Banvine) + 10ml penetrant per 10L water. 

Two or three repeat applications will be necessary at 6-8 week intervals for effective control.

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

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Management programme

Sustained control

Sustained control

Pests included in the sustained control programme are pests that are already well established in suitable habitats in Northland. These pests all cause adverse effects to the environmental, economic, social or cultural values of the region, but their distribution and/or biology means they are not suitable candidates for eradication or progressive containment programmes. Species in this programme may have rules that help to reduce the risk of further spread of these pests or reduce direct impacts on neighbouring properties. There is a focus on undertaking activities that raise awareness and providing training and advice to encourage and support community actions that reduce the impacts of these pests.
Find out more about sustained control pests

Rules

Under Section 52 and 53 of the Biosecurity Act 1993 no person can sell, propagate, breed, distribute or otherwise spread any pest in this Plan, or unwanted organism. Not complying with Section 52 or 53 is an offence under the Act, and may result in penalties noted Section 157(1).

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