The Carnivorous Plant FAQ v. 11.5
- courtesy of -
The International Carnivorous Plant Society

Q: Introduction to the sundews (Drosera)

A:Sundews are sticky flypaper plants. They bear long tentacles on their leaves, and these stalks are tipped with glands which are often brightly coloured. The glands exude attractive nectar, adhesive compounds, and digestive enzymes. Insects that land on the leaves stick fast and are digested. Often nearby glandular tentacles are stimulated and also adhere to the insect, and on many species the entire leaf coils around the prey. These motions are usually slow, taking minutes or hours to occur. An often overlooked aspect of tentacle motion is the fact that a tentacle can bend in just about any direction. But when a bug is caught on a leaf, all the tentacles know the direction to bend towards. That's pretty cool. Scientists wonder how it is done.

In some species, (for example D. burmannii), the tentacle motion is faster--some of the glands can bend 180° in just tens of seconds. Meanwhile, the tentacles of the "snap-trap" D. glanduligera move so fast they essentially fling prey into the trap center!

There are more than 180 Drosera species described, and they are found in terrestrial habitats on every continent except Antarctica. The diversity of forms in this genus is amazing. Some tropical forms grow year-round, while others die back to fleshy roots (some even hide in little potato-like corms during the dry season). Species from cold, snowy habitats often spend the winter solstice season curled up in densely packed buds called hibernacula. Some species are tall, erect or viney plants, others are ground-hugging rosettes.

Other than the usual problems associated with habitat destruction, most species do not have any particular conservation threats. I know of many, many places that once had Drosera but which have been destroyed for land development. While this can crushingly painful to watch, it is critically sad when it happens to species such as pygmy Drosera in Western Australia, because these plants have very small ranges. A single shopping mall could mean the end of a species!

In the next several pages, I will discuss all the species of Drosera, using categories similar to the ones I used in my book. If you are searching for a list of every species in the genus, or a discussion of the sections in the genus, I have that at the end of my Drosera treatment. Enjoy!

A quick comment on cultivation before we head off to the next page. As you would expect for a genus with so many types of plants, there is no single prescription for how to grow them all. You must know the kind of plant you have in order to know how to grow it. But if you have a first-time plant, it is probably one of the species that is very easy to grow, like D. capensis, D. capillaris, D. dielsiana or D. spatulata. Your main task will be to give such a plant enough light, as you will see.

Page citations: D'Amato, P. 1998a; Davion, R. 2005, pers. communication; Juniper, B.E. et al. 1989; Lowrie, A. 1987, 1989, 1999; Rice, B.A. 2006a; Schlauer, J. 2002; personal observations.

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Revised: January 2007
©Barry Rice, 2005