Drosera caduca from Bachsten Creek, Kimberley W.A.
Range: Edkins Range and Augustus Island, Kimberley, Australia
A fairly large and extremely unusual species of sundew found in a small portion of northwestern Australia, inhabiting the margins of seasonal waterways in fine sandy soils. Plants may reach 30 cm in diameter when in full wet season growth, and earn their name (from caducus) from their habit of producing two distinctive leaf types in growth. Early leaves shortly after dormancy are relatively small at only around 4 cm long, with oblanceolate petioles bearing sparse hairs on the back side and small rounded lamina; fully mature leaves however completely lose the lamina and become entirely linear or slender-oblanceolate petioles only, one of only a few carnivorous plants (possibly one of only 2 sundews) that are actively carnivorous during only a portion of their life cycle. Coloration is bright green, traps when present slightly yellow or orange tinted with white or red tentacles. Inflorescences are up to 60 cm tall, sparsely covered in hairs and bearing up to 45 blooms. Flowers themselves are up to 2 cm in diameter, with oblong white or pale pink petals sporting distinctive translucent midveins. During dormancy this species dies completely back to a bulb-like structure underground. The trap-less nature of mature plants sets this species apart from all its relatives and all other sundews as well.
Cultivation: Grow in a 3:1 fine sand/peat soil mix, kept moderately moist to wet and humid during active growth, and with temperatures of 75-95°F year round. When going dormant, allow soil to dry out almost completely, watering only very occasionally to avoid complete desiccation, until growth reappears. Sow seeds on soil surface as soon as possible (older seeds may benefit from smokewater or GA3 treatment, though this is still not reliably confirmed), and grow in strong artificial light to full sun.
Lifespan and reproduction: perennial. Reproduces through seed and natural division, and can also be grown through artificially dividing the plants or taking leaf pullings with a portion of the stem base retained.
Sources: Lowrie et al. (2017). Drosera of the World Vol. 2. Redfern Natural History Publishing.
Dying back to the dormant bulb underground. This is the most sensitive part of its season, and will rot if kept moist.