In this post we will be looking at the intricate yet distinctive qualities of Trigger Plants, Stylidiums, in the language of botany.

Stylidium is a genus of small, flowering plants with a most intriguing method of pollination.They have very rightly earned their common name “Trigger Plants”, as every flower contains a central column (trigger), that consists of the stamen and the styles, which hold the pollen sacks. These “triggers” remain in a dormant, bent position until an insect comes along and lands on the flower, at which point the “trigger” will spring forward, dousing the insect in pollen for it to transport to other flowers. I came across these fascinating plants whilst walking in the South Coast of Western Australia last year, and was captivated by their delicate yet bold character.

There are around 130 different species that exist within the Stylidium genus (plant group), most of which are native to Australia, with a few species from Asia.The most common species found in Australia is Stylidium graminifloium (Grass Triggerplant), see image at top right. As you can see from my photos, each species within this genus produce flowers that vary quite differently in their form and colour. Colours generally include a combination of white, yellow, creme or pink. The petals that make up each flower vary in size, shape and combined structure. Let’s look at S.graminifolium for example. This species produces small(petals are around 10mm in diameter), pale to dark pink “butterfly” shaped flowers that consist of four laterally paired petals. Most species within this genus produces flowers with four petals. Although, there are some rare species that produce two, three, five, even six “predominant” petals.These cleaver plants present their flowers with the petals arranged in the perfect position, so that an insect will land on the correct point every time to launch the “trigger” into action. Whats more, this arrangement ensures that the pollen sacks lands on exactly the same spot of the insect every time (So fascinating isn’t it). Some of these plans can grow up to a metre tall, although, all the species I came across were only several centimetres high and could have easily been missed if I hadn’t been looking carefully.

So next time you decide to go out walking in the Australian bush keep a look out for these fascinating plants. If you do come across one, take a moment to have a good look at the unique details that so define these remarkable plants.

Trigger plants Part 1