Crocosmia x crocosmiiflora

Origin: South Africa
Size:  60cm to 90cm H
Flowers: December to April
Fruits: December to April
Best time to remove: October to April

What it does

Montbretia invades gardens, bushland, roadside areas and stream sides. It tolerates all conditions and can take over and displace indigenous grasses, groundcovers and over-storey regeneration.

Montbretia is a perennial herb which dies back annually. It is grass-like in appearance and often mistaken for Watsonia. Montbretia features strap-like flat leaves around 30 – 80 cm long and 1 - 2 cm wide. It was a popular garden plant due to its bright orange trumpet-shaped flowers, which form in two rows along each stem.

New growth is produced in early spring and small bulbils can be produced from the flower base. The fruit is a 3-lobed brown capsule that produces few seeds.

How it spreads

  • ·natural regeneration is usually next to the parent plant from corms that spread rapidly underground to produce new plants.
  • as a result of ground disturbance, dumping of garden waste and by attaching to machinery.
  • it is often sold in nurseries, fetes or market stalls.


The most effective time to remove Montbretia is just before full flowering occurs around spring and summer and/or digging out bulbs when the soil is wet.

Remove by Hand

Hand removal is only practical for small clumps of the weed. Use a garden fork to dig all corms and underground stems to ensure complete removal. Cut stems first if the plant is in seed.

Spray with Herbicide

Montbretia can be sprayed with a glyphosate-based product or alternatively you can swipe leaves with poison using a dabber bottle.

Dig Out

Dig out patches of Montbretia weed carefully when soil in moist as corms break off easily; corms often form linked chains.

Indigenous alternatives to plant

Many clumping alternatives indigenous to the Yarra Ranges region are available and would make great substitutes for Montbretia. Some alternatives include:

Tasman Flax-lily, Dianella tasmanica

Pale Flax-lily, Dianella longifolia

How to dispose of weeds

By disposing of environmental weeds correctly you can prevent re-infestation on your property and elsewhere.

  • Landfill (Weed Wipeout Tip vouchers available for some species).
  • Green waste bins ensure that weeds are not able to spread.
  • Woody weed stems can be bundled for green collection twice per annum.
  • Composting (excluding seed heads or species with vegetative reproduction, e.g. Wandering Trad).
  • Burning in accordance with Council and the Country Fire Authority (CFA) prescribed burning periods and regulations.
  • Recovery and transfer stations available for weed tipping are Healesville, Wesburn, Coldstream, Lysterfield and Montrose.

Using chemicals

Non-chemical treatment is often the most effective and safe option especially on smaller scale infestations.

Where chemical use is undertaken:

  • Always follow the manufacturer’s guidelines when using chemicals.
  • Wear protective clothing and eyewear.
  • When purchasing your herbicide, always ask for a Materials Safety Data Sheet (MSDS) or refer to the manufacturer’s website for specific safety guidelines and information.
  • Some herbicides will kill other plants and not just the target species.
  • When used near waterways herbicides can be very poisonous to aquatic life.
  • Use chemicals sparingly and be sure that you are using the right chemical and application technique.
  • Ensure the weather conditions are suitable (e.g. minimal wind and no rain expected).
  • Apply herbicides at the correct time during the plant’s growth cycle so you get the best results.