Plant: dull grey green with yellow flowers

Close up of leaf and leaves alternate

Leaflets on stem at leaf axis

Buds and flowers

Funnel-shaped flowers

Flowers have 5 petals

Immature fruit is green

Fruit at varying stages of maturity

Young plant from above

Close up of reshooting cut stem

Scientific Name

Cestrum parqui L'Her.

Common Names

green cestrum, green poison berry


Central and South America



Distinguishing Characteristics

This can be a large woody shrub. Its new shoots and leaf axis may have some hairs. Mostly this plant is hairless. Small leaves/leaflets may also be found at the leaf axis. When crushed this plant has a strong, distinctive and somewhat unpleasant smell.

Leaves are alternate, narrow and lance shaped, 2-7 cm long, usually 1-3 cm wide; the leaf stem (petiole) can be up to 1 cm long. Leaves are a grey/green colour and are a paler shade underneath.

Inflorescences (groups of flowers) are formed at the end of the stems. Flowers are funnel-shaped, either sessile (have no stalk) or on pedicels (on the stalk) and greenish yellow in colour. Flowers can be found on this plant throughout the year.

Fruit is egg-shaped, to about 10-15 mm in length and is a black berry when ripe.

This plant is very difficult to kill. It usually responds best to herbicide (such as Roundup) when it is applied at 100% strength, to long scrapes along the stem. To scrape the stem: take a knife and drag it up and down the stem revealing the white inner layer. Depending on plant size, scapes could be 10cm - 30cm in length. Herbicide should be applied to the wound within 10 seconds.


Other plants easily confused with this plant

This plant is very distinctive, especially when a leaf is crushed and smelt.

Sources & References

"Weeds - an illustrated botanical guide to weeds of Australia" by B. A. Auld and R. W. Medd

"Plantnet FloraOnline"  (2005)

 South Coast Weeds


Prepared by Justin KY Chu, July 2005

Checked by IEWF, January 2006

Checked by Barbara Wiecek, Botanic Gardens Trust, Sydney, June 2006