Floating Fern

Floating Ferns are tender aquatic perennials with light-green fronds. The short rhizomes creep beneath the surface while the round foliage unfolds lengthwise on top. Concave, evergreen leaves show a prominent midrib and measure about 1 cm in diameter. Stiff hairs build some sort of cage that encloses an air bubble repelling water from the surface. This way the plant floats on standing water or along banks of slow flowing streams. Different from its land-living relatives the Floating Fern grows its sori (containing the spores) on the upper surface. They are released from sporocarps that are branched like a corymb. Slowly but steadily growing the plants form dense mats that blanket the water densely about 5 cm thick. They originate from tropical America but easily naturalise in frost-free climates. These ferns are considered invasive in some regions like Australia and New Zealand. Treatment with pesticides are a challenge on water, since most substances affect fish and the ferns easily associate with other aquatic plants such as water lilies. Using this plant one should be aware that it might escape cultivation easily, although in smaller ponds in private gardens in Riyadh, they are easily controlled. The attraction of Floating Ferns are minute, exotic fronds. It grows fastest in full sun, but in Riyadh will do better in partial shade. The water should be high in nutrients, but the plants thrive in almost any environment. Propagation is extremely simple by division.