Three Purple-Flowered Utrics. from Near Esperance, Western Australia

Utricularia dichotoma

As I mentioned a few days ago, I ran across a fantastic blog about wildflowers near Esperance, Western Australia. Today, I wanted to do a post on three species of Utricularia - Utricularia dichotoma, Utricularia violacea, and Utricularia volubilis - which are found in that area. I grow one of those, Utricularia dichotoma, and find it an easy species following my standard growing guide.

Utricularia dichotoma bladders

The widespread Utricularia dichotoma occurs throughout southern Australia, and is locally known as "Fairy Aprons." In Western Australia, U. dichotoma grows as an affixed aquatic in more-or-less permanent freshwater ponds. Around Esperance, these are created by roads being built across swampy ground, creating mini-dams, which hold water throughout the dry season. (Thus making this one of the few times human intervention has helped carnivorous plants!)

Utricularia violacea

Utricularia violacea commonly grows alongside U. dichotoma as an affixed-aquatic, but often in shallower areas which tend to dry during the hot, dry summer. Unlike U. dichotoma, U. violacea is a diminuative annual. It is sometimes confused with Utricularia inaequalis, which has similar, but larger flowers (about the size of a thumb nail). As you can see from the picture above, U. violacea's flowers are much smaller.

Utricularia volubilis

Rarer than either U. dichotoma or U. violacea, Utricularia volubilis is a perennial well known for its large, showy flowers which perch atop long, twining stalks. These flower stalks can grow up to 3 feet (1 meter) in height. In summer, it dies back to a corm. As with other Western Australia natives, U. volubilis requires summer files to clear out competing, non-carnivorous plants. As with many other Western Australian natives, its range is probably much larger than Lowrie reports.

U. volubilis flowers when the water level is approximately at ankle level above the substrate, making it an affixed-aquatic, like U dichotoma and U. violacea. The base of the plant is usually submerged for most of the year, and the large (5 mm) bladders often capture aquatic prey. Its flowers often appear in pairs, like U. dichotoma.