Worldwide, the Droseraceae are the most diverse of all families of carnivorous plants with nearly 200 species and countless native hybrids as well as cultivars bred for their spectacular leaves and lovely flowers. But if you really want to see sundews, go to Australia, no bogs required. You will need your iNaturalist Ap to help identify everything you find. Most sundews are perennials, living up to 50 years, but some are annuals or biennials, dying after blooming. They grow in nitrogen-poor soils on every continent except Antarctica, originating in Australia and South Africa. Adaptations to drought and flooding include tubers, corms, and hibernacula — a core of hard, unfurled leaves tolerant of freezing and dehydration. All our North American species form hibernacula to survive winter.
Insect entrapment involves active movement of tentacles. In the catapulting species (see the Pimpernel Sundew below), the outer tentacles flick the insect into the center of the leaf where stickier tentacles then wrap around the victim. In many species, entire leaves curl into a ball of digestion. The sticky gel that gives all sundews their name not only exhausts the insect but also suffocates them by clogging their respiratory openings. Death can occur in as little as 15 minutes with acids and digestive enzymes secreted by the plant almost immediately.
No wonder Charles Darwin loved these plants! His research showed that true digestion occurs as an evolutionary adaptation to nitrogen-poor soils. The roots of most species do little more than anchor the plant and absorb water. Nutritional needs come from the entrapped insects. And, like most every carnivorous plant, the flowers tower above the insect-eating leaves to keep pollinators safe. Now that you are as excited about sundews as Charles Darwin, here are some cool videos and a few of my photographs, including one of our own Round-Leaved Sundew. All the pictures below are of sundews that I saw in New Zealand recently.