Azolla caroliniana (Carolina Mosquito Fern) is a tiny floating fern forming a mat of prostrate and freely branched stems covered with bilobed scale-like leaves arranged in two rows. The upper leaf floats on the surface and the lower leaf is submerged. The pale green to blue-green foliage turns bright red in response to stress such as very bright light or very high or low temperatures. Small feather-like roots are produced along the lower surface of the stem and hang freely in the water. Native to North America, Carolina Mosquito Fern occurs naturally in ponds and lakes, in slow-moving streams, in canals, and in backwaters and sloughs. It grows extremely quickly under optimum conditions and can sometimes become a nuisance. It can form thick mats that completely cover the surface of the water, preventing mosquitoes from depositing their eggs. A unique trait of Carolina Mosquito Fern is its ability to fix atmospheric nitrogen into a usable form. This is done via a symbiosis with the cyanobacterium, Anabaena azollae. Nitrogen is one of the 3 vital macronutrients required for plant health, so this species can be used as a biofertilizer. Carolina Mosquito Fern is cultivated as an ornamental plant for use in water gardens, aquaria, and ponds.

• This deciduous perennial spreads indefinitely.
• Performs best in full sun to part shade in water gardens, ponds, or aquatic containers.
• Virtually pest and disease free.
• Reduce its spread by removing portions with a net.
• Propagate by redistributing clusters of plantlets when they appear.
• Native to North America.