Agapanthus

BUSH INVADER

Agapanthus praecox ssp orientalis

family: ALLIACEAE

Description

  • Hardy perennial lily from South Africa. Grows in thick clumps, tough, hardy, likes full sun, grows in almost any soil, almost anywhere. Also called Lily of the Nile.
  • Leaves are thick, succulent, dark glossy green and strap-like, to 50cm long, and poisonous. There is a weedy miniature or dwarf variety, and a number of cultivars, which should also be closely watched for invasive qualities.
  • Large, rounded heads of massed tubular flowers, blue or white, top a strong thick stem, to 1.2m tall, in summer.
  • Numerous small black shiny seeds are produced in a 5cm three-sided capsule, end of summer into autumn.
  • Roots are fleshy, crowded, strong and tenacious.

Dispersal

The underground structure (rhizome, poisonous) forms large continually extending clumps, and seed washes down waterways. Agapanthus is also frequently dumped on bushland edges.

Impact on Bushland

Spreads rapidly down drainage lines, but will also grow in dry areas. Dense clumping roots displace all other vegetation.

Distribution

Throughout the Blue Mountains.

Alternative Planting

Native Plants
Spiny-headed Mat Rush (Lomandra longifolia)
local native flax lilies (Dianella species)
Saw-sedges (Gahnia species)

Exotic alternatives
Pride of Madeira (Echium fastuosum)

Control

Cut the flower heads before the seeds form, while they are still green and sappy.
Dig out clumps with a mattock. Try to get most of the roots.
Pull seedlings by hand from moist soil when very small.
Does not respond well to herbicide, but can be treated by cut and paint: crown, and apply herbicide instantly, before sap bubbles out.
Follow-up weeding of seedlings and shoots from rhizomes will be necessary.

Pictures of removed Agapanthus
Some of the mountain of Agapanthus removed by Green Corps workers from World Heritage bushland adjoining the Conservation Hut, Wentworth Falls.

Picture of Agapanthus

Agapanthus: large rounded head of tubular flowers, produced in summer

Agapanthus spreading into bushland from a nearby garden

Flower heads are borne on a stout stem rising from a basal clump of glossy strap-like leaves.

Dense clumping roots of Agapanthus displace all other vegetation

All through the Blue Mountains dense plantings of Agapanthus line the roadsides, seeding into the stormwater system and ending up in bushland.