Several months ago a friend of mine introduced me to Stylidium debile, most commonly referred to as the “Frail Triggerplant.” S. debile is a perennial plant native to Australia and is found in swamps and wet coastal areas; primarily the Eastern coast. It is hard to believe at first glance that scientists speculate this plant may be carnivorous. Triggerplants were named based on an interesting mechanism located on their flowers that enhances pollination. When an insect lands on a flower it causes an appendage (which resembles a tiny arm holding a handful of pollen) to rapidly swing around and harmlessly strike the insect with the “handful” of pollen. I can only imagine this mechanism frightens the holy hell out of the unsuspecting insect and causes it to fly away, covered in pollen; thus allowing the plant to spread its genetic material. I recorded the video below to demonstrate. Watch closely, it is easy to miss!
Description: “Perennial herb with a loose rosette of leaves at apex of a short stem, often with scattered several smaller leaves below. Leaves spathulate to obovate, 0.5–3 cm long, 4–8 mm wide, margins entire, lamina glabrous. Scapes 5–35 cm high, sparsely glandular-hairy; inflorescence glandular-hairy. Sepals c. 1 mm long, shorter than the ovary. Corolla 2–4 mm long, pink, whitish, bright mauve or reddish, slightly glandular on the outer surface; tube slightly longer than sepals; petals not quite equal. Column c. 4 mm long. Ovary oblong, 1.5–2 mm long, glandular-hairy. Capsule narrow-oblong, 6–8 mm long, often ± curved; seeds tawny, hairy.” CITATION
Cultivation: I am successfully growing this plant in the same conditions as subtropical Drosera using a 1:1 mixture of high quality peat moss, and silica sand (pool filter sand). You could also probably use (live or dried) long-fibered sphagnum moss, or a 2:1 mixture of peat moss to perlite. The plant pot sits in a tray of distilled (very low mineral content, preferably 0 PPM) water, and is kept permanently wet. A 2-bulb T5-HO fluorescent light fixture is located roughly 12-15 inches above the plant; and it receives about 12-15 hours of light per day. Once a month or so I lightly spray the plant with a very dilute Maxsea 16-16-16 fertilizer. I doubt the plant truly needs fertilizer; I often forget to fertilize it and it continues to grow like a weed. In fact I once picked up the pot to inspect the plant and found several inches of roots and a plantlet growing out the drainage holes; completely submerged in water! I would not be surprised if this plant could easily be grown on a very bright windowsill in the average home sitting in a dish of pure water.
Carnivory: There is some debate about whether Stylidium debile is a “fully carnivorous” plant. It has been discovered that certain parts of the flower, and the stem have glands that produce mucilage (sticky goo). These glands have been shown to not only be able to trap insects (much like Drosera), but that these glands also produce enzymes that can break down protein called protease (“PRO-tea-aze”) Darnowski et al. 2006 One theory is that Stylidium debile is a form of “Protocarnivorous Plant.” You can think of it as a “prototype.” This theory argues that S. debile is evolving into a fully carnivorous plant. Only after additional research is performed (demonstrating the plant’s ability to absorb nutrients from the captured prey) will we know whether Triggerplants are best classified as protocarnivorous or if they are able to claim the title “Carnivorous.”
Either way I recommend growing this neat plant; for the foliage, ease of care, and the flowers!
For Further Reading: