WINTER is enlivened by the appearance on damp sandy soils of sundews (droseras), which in spring put forth minute white or pink blooms, becoming dormant in late summer. These small carnivorous perennials usually grow in nitrogen-deficient soil, so need to lure insects to supplement their diet.
The tentacles on sundews' leaves are active traps because they move to enfold their prey ... A mosquito or gnat becomes entangled within a few seconds even if it touches only one tentacle. Its struggles not only bring it in contact with other tentacles, but each tentacle transmits a stimulus to others, and in response they too will bend through an angle of 100 degrees towards the centre to help enfold the victim.
... each tentacle secretes in the gland at its tip a digestive juice. Over a period of days the soluble matter of its prey is reduced to a fluid that is absorbed by the plant. The tentacles then assume their first position, fanned out and gluey tipped, ready to trap the unwary. The dry husks of the earlier victims drop lightly from the leaf and the table is set for another meal (Erickson, R, 1978).
Many droseras are believed to be poisonous to livestock, and most have tubers. Dyes and stains are obtained from the pressed plants or tubers; indeed, early settlers used these for ink.
Worldwide there are 90 sundews, 56 of them in Australia; 80 per cent of these are confined to south-western WA. We are fortunate in Victoria to have seven species.
Widespread and found in all states but Queensland, the sweetly perfumed climbing sundew flowers from June to October. Stems are up to 600mm, trailing over low shrubs and up into higher bushes, the leaves round and long-stalked. The large white flowers are showy, one of the first flowerers in the Wonthaggi Heathland at the end of winter.
Found in all states and widespread, the forked sundew flowers from spring though summer, mainly in wet places. It is found in the Wonthaggi Heathland and around streams and ponds in Wilsons Prom. Leaves are 50-450mm long, narrow pale green to reddish, erect and strap-shaped, the blade forked into a Y, the arms fringed with sensitive hairs. The erect flower stalk is often larger than the leaves, with a branched cluster of cupped white flowers.
Occurring in south-east Australia and New Zealand in damp sands and heathlands, this tiny jewel flowers in spring and summer, generally in coastal areas. It has a minute rosette of round or spoon-shaped leaves, usually pinkish. The tiny white single flowers are on stalks up to 45mm long. They grow in conjunction with Hundreds and Thousands, Stylidium inundatum, around trackside water in the Wonthaggi Heathland.
Found in all Australian states, Sri Lanka, S E Asia, Japan, Papua New Guinea, this sundew inhabits a variety of sites, including dry sand. It has a basal rosette of pale green round leaves and produces hairy flower buds and white/pale pink flowers from August to January; these flowers rarely open until noon. This is a common sundew in our area, its seeds ovoid and less than 0.6mm long. It has a greener appearance and smaller flowers than its cousin, tall sundew, but it is difficult to distinguish them in the field.
(= ear-like lobe)
More prolific in Gippsland and found in south-east Australia and New Zealand, it has similar habitats and seasons, but differs in that it can reach 300mm in height, its cup-like flowers are pink, it has smooth buds, the linear seeds are up to 1mm long and it often lacks a basal rosette.