Salvinia natans

Common Name: salvinia 
Type: Fern
Family: Salviniaceae
Native Range: Southern Europe, northern Africa, Asia
Zone: 10 to 11
Height: 0.25 to 0.25 feet
Spread: 0.25 to 1.00 feet
Bloom Time: Non-flowering
Bloom Description: Non-flowering
Sun: Full sun to part shade
Water: Wet
Maintenance: Medium
Suggested Use: Annual, Water Plant, Naturalize, Rain Garden
Tolerate: Rabbit

Culture

Grow on still water in full sun to part shade. Scatter small bunches of plants on the water surface after last frost date. Spreads quickly in optimum conditions. Net out excess plants as needed. Can be quite an aggressive spreader in frost-free climates. Sporocarps sink to the bottom of the water body in fall for overwintering, and rise to the surface in spring only after temperatures warm up. In home water gardens in the St. Louis area, some plants should be lifted in fall each year before first frost and overwintered in a saucer of moist soil covered with 2” of water in a bright frost-free area or in an aquarium.

Noteworthy Characteristics

Salvinia natans, commonly called salvinia or water fern, is a deciduous, free-floating, rootless, aquatic perennial fern that forms rapidly expanding mats of foliage (to 1” tall) on still water surfaces. It is distinguished from the similar Azolla filiculoides (mosquito fern) by having longer leaves (to 3/4”) which are unlobed and hairy, simple mostly unbranched stems and no true roots. Leaves are in whorls of three. Two elliptic, light green leaves appear on the water surface and the third leaf (which performs root functions) is heavily dissected and submerged. It is a popular addition to water gardens and ponds. This fern is native to Europe, Asia and northern Africa. Plants in the genus Salvinia are sometimes commonly called water spangles.

Genus name honors Antonio Maria Salvini (1633-1729), professor of Greek at Florence, who helped Micheli in his botanical studies.

Specific epithet means floating.

Problems

No serious insect or disease problems.

Garden Uses

Free floating aquatic perennial for water gardens or ponds.