Balsam (busy Lizzie)

Impatiens spp. (walleriana)
Herb
Alternate
Simple
Multi-coloured
Green
Red

Genus of 450 species of succulent annual plants, mostly native to the tropics of Asia and Africa. They have white, red or yellow flowers and seedpods which, when ripe, pop and scatter their seeds. Some species are known as touch-me-not.

 

Common names 
Also known as: busy lizzie, touch me not, garden impatiens, Japanese balsam, jewel weed,
Family 
Balsaminaceae
Deciduous 
No
Flowering time 
Spring to Autumn
Native/Exotic 
Exotic
Origin 
Native to the tropics of Asia but has long been cultivated in temperate regions of the world.
Notifiable 
No
State declaration 
Nil
Council declaration 
Class R – Reduce populations
Known distribution 

Naturalised in some parts of eastern Australia (i.e. in south-eastern and northern Queensland and in the coastal districts of New South Wales).

Also widely naturalised in other parts of the world, including south-eastern USA (i.e. Florida), La Réunion and several Pacific islands (e.g. New Caledonia, the Galápagos Islands and Hawaii).

Habitat 

Grows in bushland, along water courses. It has also been found at a couple of locations on moist, shaded road verges, moist remnant bush on drainage lines and around shady wetland margins. In Queensland the plant is naturalised on basalt soils in Palmerston National Park. It colonises forest margins and is displacing native fern communities around waterfalls. It has also naturalised in riparian habitats and other moist areas in South East Queensland. Its brittle stems are easily broken and carried downstream by floodwaters. It is used as an ornamental in Australia.

Habit 

A short-lived (i.e. annual), or occasionally long-lived (i.e. perennial), herbaceous plant with upright (i.e. erect) stems usually growing 30-80 cm tall, but occasionally reaching up to 1 m in height.

Impact and control methods 

Impatiens (Impatiens walleriana) is regarded as an environmental weed in Queensland and New South Wales, and as a "sleeper weed" in other parts of Australia. This species has escaped cultivation and has often become naturalised in riparian areas and native bushland near habitation. It is probably most common in south-eastern Queensland, where it is ranked among the top 200 most invasive plant species.

Impatiens (Impatiens walleriana) is mainly naturalised in riparian habitats and other moist areas in south-eastern Queensland. It has also been recorded in Palmerston National Park in northern Queensland, where it has colonised forest margins and is also displacing native fern communities around waterfalls.

This species is also naturalised in bushland and around habitation in the coastal districts of New South Wales. It appears on several local and regional environmental weed lists in these parts of New South Wales (e.g. in Warringah Council, Pittwater Council, Lismore Council, the Sydney North region, the NSW North Coast region and the wider Sydney and Blue Mountains region) and has been recorded in some conservation areas throughout the eastern parts of the state (e.g. in Billinudgel Nature Reserve and Tunnel Gully Reserve). Impatiens (Impatiens walleriana) is also listed among the invasive weed species that threaten the integrity of particular stands of endangered littoral rainforest in New South Wales.

Stem and leaves 

The young stems are greenish or reddish and translucent, mature slightly thickened and woody at the base. The stems can branch vigorously. The leaves are spirally arranged, glabrous (without hairs or scales), somewhat fleshy, broadly elliptical or ovate to oblong-elliptical or oblong-ovate, 4-13 cm long and 2.5 -5.5 cm wide, with 5-8 pairs of lateral veins and 1-2 (sometimes more) extrafloral nectaries (glands outside the flower) along the petiole (leaf stalk). Leaf margins coarsely toothed.

Flowers and fruits 

he flowers appear predominantly in pairs or threes at the leaf-stem junction in the top part of the plant. They may be in different shades of pink, rose or red, sometimes also white, 5 petalled, about 3 cm in diameter. Upper petal crested, lateral petals fused towards base. Flower stalks 3-5 cm long. Lateral sepals 2, small, green, 3-7 mm long. Lower sepal whitish, shallow, abruptly constricted into 3-5 cm long narrow spur. The flowers appear  throughout the year. The fruit is a smooth greenish capsule, 15-20 mm long and 4-6 mm wide, swollen in the middle. Ripe fruits explode with even slight push and eject small brownish seeds.

Reproduction and dispersal 

This species reproduces mainly by seed, however pieces of its succulent stems will readily take root if detached from the rest of the plant.

The seeds are spread shorter distances when they are ejected from the mature fruit. They may also be spread by water. Seeds and stem segments are also dispersed in dumped garden waste

Similar species 

There are suitable alternatives to this plant on the the Grow me Instead website