Agave americana

Century plant

Family: Agavaceae

Origin: Mexico

Flowering century plant on a bank.
Century plant produces a large woody spike with many yellow flowers.

Regional Pest Management Plan (RPMP) status

  • Whole region — Sustained control
  • Hauraki Gulf Controlled Area Notice pest

View more about the RPMP statuses

General description

Succulent perennial. Leaves are fleshy, < 2 m long, sharply toothed, dull green or variegated, and formed in basal rosette. Flowers are yellow and borne on flowering stalk in late summer – early autumn.

Seed capsules are oblong and contain shiny black seeds. Basal rosette dies after flowering and is replaced by several small lateral rosettes.

What you need to know

To help protect our environment, from 1 September 2021, you:

  • will not be allowed to breed, distribute, release or sell century plant within the Auckland region.
  • will not be allowed to plant century plant within the Auckland region, unless you are transferring an existing plant on your land to another location within the boundaries of the same property.
  • must destroy any century plant on land that you occupy if it has been planted in breach of the above rules and you are directed to do so by an authorised person.

Habitats

Coastal ecosystems, sand dunes, cliffs, grasslands, open sites, disturbed sites, roadsides, pasture, open canopy forest.

Dispersal

Sets seed. Vegetative spread from rosettes and stem fragments. Seeds and vegetative propagules dispersed by gravity and water. Human-mediated dispersal through dumping of garden waste and deliberate planting.

Impact on environment

Forms dense patches in coastal ecosystems, suppressing native vegetation.

Control

Site Management

Follow up treated areas 3 times per year. Encourage natural regeneration of native plants or replant treated areas where possible after 2-3 treatments to establish dense ground cover and minimise reinvasion.

Recommended approaches

Physical control

Method: Dig out.

Plant parts requiring disposal: All parts.

Disposal options: Remove to greenwaste or landfill if practical.

Biocontrol

Biocontrol is currently not available for this species.

Community agrichemical control recommendations

Basic Growsafe certified:

For small infestations: Foliar spray with 3g metsulfuron-methyl plus 150ml glyphosate per 10L of water.

Certified Handler/Experienced agrichemical user:

For medium to large infestations: Foliar spray with 3g metsulfuron-methyl plus 150ml glyphosate per 10L of water and 10ml penetrant.

Safety notes

Plant has spines.

Caution: When using any herbicide or pesticide please read the label thoroughly to ensure that all instructions and safety requirements are followed.

Spiky leaves of the century plant.
The leaves are up to 2 m long, are fleshy and triangular in cross section.
Photo credit: Weedbusters