Post last updated: February 7th, 2019
Originating in China, Rainbow Fern or Rainbow Moss, Selaginellaceae uncinata, is also known as Peacock Fern, Peacock Moss, Peacock Spikemoss, or Blue Spikemoss. Apparently, the 700 species of the genus Selaginella can have 3 or more different names for each species.
Some Selaginellas are native to Florida with great drought tolerance and ability to withstand the sun but the Selaginellas most often cultivated are those from Africa and China. Selaginellaceae uncinata is non-native and has been found growing wild in 4 different counties where wetland areas exist. See Atlas of Florida Plants. Dave’s Garden has an article and photos of other varieties under Other Species of Selaginella. Of course, the Golden Club Moss, which has a similar growth habit, caught my eye but I haven’t seen one in local stores.
It seems they aren’t really mosses or ferns but Fern-Allies and share a similar reproductive pattern of no flowers, fruits or seeds, just inconspicuous “seed cones” filled with both microspores (sperm) and megaspores (egg). I have never noticed these on my plants so they must be truly inconspicuous.
It is a perennial evergreen that forms a dense mat of tiny, almost papery iridescent blue-green leaves with touches of red and orange. Two things are imperative in growing a Rainbow Fern:
(1) Keep it in the shade. The deeper the shade, the more the fronds will turn blue-green.
(2) Keep it moist. If you allow it to dry out, immerse the plant in water and it may bounce back. A light fertilizer application once a week from spring to fall is sometimes recommended but I never got around to it.
Three foot streamers sprawl and hang nicely over containers and hanging pots, and it looks good indoors including terrariums. It is sometimes used as a ground cover that can withstand light foot traffic but caution is advised as it can be aggressive. My friend at Deb’s Garden planted hers in the ground, in her woodland garden, in 2015. Since then, it has spread to approximately 3 feet by 2 feet and only in the area where she planted it. The invasive possibility has kept me from growing it in anything but a ceramic pot because I’ve had aggressive plants that were fine for years and suddenly spread over a wide area.
Other uses for it: alpine and rock gardens, waterside gardens.
I discovered my first Rainbow Fern at a local arts festival. First identified as a Rainbow Fern, rather than any of the other common names attached to it, means it will always be a Rainbow Fern to me.
The acquisition of my second Rainbow Fern was like a scene out of a sappy romance movie. I was in Wal-Mart wheeling a buggy around the bedding plant section when I saw it hanging across the room. My eyes bugged out because Wal-Mart was the last place I ever expected to find a Rainbow Fern. I could see there was only one which prompted me to punch the gas on the buggy. I careened around corners like a cartoon character until that Rainbow Fern was safely in my buggy.
I propagate by cuttings planted in moist soil and kept moist.
I am currently without a Rainbow Fern. You absolutely, positively can not let them dry out. Even moisture is imperative.