Common Australian Garden Weeds

Urtica urens

Scientific name: Urtica urens L.


Habit of stinging nettle (Urtica urens).


Stinging nettle in the early stages of flowering, with obvious stinging hairs present on the leaves.


Close-up of the serrated leaves and flowers of stinging nettle.


Close-up showing stinging hairs on the reddish stems and petioles (leaf stalks) of a stinging nettle plant. There are also flowers present in the axils of the oppositely arranged leaves.

Common names: Stinging nettle, small nettle

Family: Urticaceae

Origin:

Cosmopolitan.

Habit:

Annual herb erect herb growing 30-60 cm tall.

Habitat:

Weed of wasteland, stockyards and overgrazed pastures.

General description:

Stems and leaves

Plants are bright green with scattered transparent stinging hairs on stems and leaves.  The stems are otherwise hairless.  The leaves are covered in soft hairs on both surfaces as well as having longer stinging hairs.  Leaves are opposite with stalks (petioles) 0.2-3 cm long and oval blades 0.9-4.3 x 0.5-3.5 cm with deeply incised margins which are unevenly serrated.

Flowers and fruit

Plants produce separate male and female flowers.  The inflorescences are clusters of small,  4-lobed green flowers on short 'spikes' up to 1.5 cm long. Flowering occurs in late winter or spring.  The 'seeds' are elliptic 1-2 mm long.

Distinguishing characteristics:

Annual herb 30-60 cm tall with bright green opposite leaves that have irregularly incised toothed margins. Plants are covered in stinging hairs and so must be handled with extreme caution, protective clothing is recommended.

Noxious status:

Not noxious.

Sources:

Kleinschmidt, H.E., Holland, A. and Simpson, P. (1996). Suburban Weeds. 3rd Edition. Department of Primary Industries, Brisbane.

Stanley, T.E. and Ross, E.M. (1983-1989). Flora of South-eastern Queensland. Volume 1. Department of Primary Industries, Brisbane.

Auld, B.A. and Medd, R.W. (1996). Weeds: An Illustrated Botanical Guide to Weeds of Australia. Inkata Press, Sydney.