Floating water plants are the ultimate in easy care water gardening!

There is no potting necessary for these plant's. The plants will just drift in the pond. Their roots dangle down into the water, drawing nutrients for the plant's growth. They act as the pond's feather dusters, removing suspended particles from the water. Also these plants are important for shading the pond to protect fish and other wildlife from baking under the hot sun. The plants also provide a way for wildlife to hide from predators. Floating plants are fertile spawning grounds in the spring and hideaways for the young fry that hatch and grow in summer.

Plants that grow on the water's surface have developed special means to keep themselves afloat. Some, such as water hyacinth, have enlarged air sacs in their leaves to keep them afloat. Others, such as frogbit, use repellent waxes to keep the water from being absorbed into their foliage. Still others, such as water lettuce, have water repellent hairs that use surface tension to allow the leaves literally to stand on the water. All floating plants use their ability to float to exploit an environmental niche. Growing in water that is too deep for other plants or that appears only seasonally, such as floodwater in order to grow in water that is rich in nutrients.

Larger floating water plants, such as the sensitive plants, water lettuce, and water hyacinth, grow well in ponds of all sizes. Keep them in the top of a stream or waterfall to aid in biological filtration. Smaller plants are more appropriate for container or container and tub gardens. In large, earthen ponds, it takes quite a few to make an impression. Floating plants are best not permitted to completely cover a pond's surface. Too many plants can reduce oxygen in the water levels that are dangerous to fish and other underwater animals. Very general rule is that one third of the pond's water surface should be covered with vegetation. You can also use rubber rings that you can buy from pond suppliers to keep your floating plants from going into the skimmer, or other unwanted area's.

Most floating water plants grow well in full sun. Many also grow well in part shade, water fern and water lettuce would be an example. Floating water plants are very sensitive to salt being added to the pond, salt quickly dries out the plants. Floating water plants absorb nitrates and phosphates from the water. Water hyacinth and water lettuce, in fact, are so efficient that they are often recommended to aid filtration.

Floaters that require warm summer temperatures should not be placed in the pond until the water temperature has reached a consistent 65 degrees. If the water falls below 65 it can cause the foliage to yellow and form black streaks.

Most floating plants are propagated by dividing off new growth that is produced on side shoots. Once the new growth has developed enough roots to support itself, it can be detached from the main plant. Fish can be a problem because they tug on the plant's roots and tear at their leaves. Koi are probably the most prevalent pest of water hyacinth and water lettuce. Deer, raccoons, and muskrats also like to munch on these leaves.

Aeschynomene flutians, giant water sensitive plant	Giant water sensitive plant has long, 1-3 inch leaves that grow alternately on a single stem. This stem floats on the water, becoming swollen, white, and somewhat furry as it ages. The plant's summer blooming, large 1 inch flowers are yellow and resemble blossoms of the common sweet pea, although they have no fragrance. Leaves are sensitive and close when touched. A quick grower, it is native to warm regions of the world and may be grown free-floating or rooted to the edge of the pond with its stems trailing out on the water surface. It grows in sun to part shade and reaches 2 inches high with a running spread. Giant water sensitive plant propagates by division or cuttings. It may also be grown from seed sown on moist soil, which usually sprouts in a few weeks. To overwinter the plant, make sure to keep it in water that is frost free, preferably above 60 degrees. Mealybugs and spider mites may affect the plants, mostly in winter. Hardy in Zones 9-11.
Azolla, Azollaceae	A true fern, this aquatic has leaves that are fuzzy and finely toothed. A bright green in summer, leaves turn red in spring and fall when the water is cool. Excellent pond cover for fish and other wildlife. Azolla species hold a blue-green algae that fixes nitrogen, fertilizing plants, so be sure to put any that are skimmed from the pond into the compost or use as a mulch in the perennial garden. Azolla species are very sensitive to the number of daylight hours they receive, giving them a tendency to die out during the shorter days of winter. They grow in sun to shade, reaching 1/2 inch high with a running spread. Hardy in Zones 9-11.
Azolla caroliniana, fairy moss, mosquito fern	Fairy moss is native to North America. It can be found growing wild as far north as Michigan and Wisconsin and into the New England states. Plants are rounded, no tirangular, like branches of aborvitae (Thuja). They overwinter by freezing in the ice and thawing in spring.
Azolla pinnata, Christmas tree fern	A species native to South America, Azolla pinnata has triangular shaped foliage that looks something like a flat Christmas tree. It is considered invasive and is prohibited under U.S. federal law. It will usually die in winter since it depends on long hours of daylight.
Ceratopteris thalictroides, water fern	Leaves of this unusual floating plant look like big, puffy leaves of italian parsley. The plant is said to resemble a fern because of its highly cut and serrated leaves. It usually reaches 12 inches high and wide. Any part of the foliage that lies on the water surface sprouts a plantlet and will root to become a new plant. Water fern also grows in soil in a few inches of water. It grows best in full shade, and needs at least part shade to survive. To overwinter water fern, which is hardy in Zones 9-11, keep it in water of at least 65 degrees. Bring it indoors into a warm fish tank. It is not bothered by pests or diseases.
Eichhornia, water hyacinth	Well known for lavender-blue flowers and shiny green foliage, the tender floating aquatic. Leaves are spongy and inflated at the base, making them float in the water. Plants reach about 12 inches high with a running spread. Water hyacinths also make great container plants, just drop them in any pot that will hold water, throw some fertilizer in, and be rewarded with tons of flowers for the entire summer. The thick, long roots of water hyacinths are black and feathered. Trim them back or thin periodically so that older roots do not start to decompose in the pond or clog filtering systems. Hyacinths are grow best in sun to part shade om warm water and will not survive a winter freeze. They are hardy Zones 9-11. So you will want to wait until water temperature is consistenly 65 degrees before putting them into the pond. In southern states, the plants are considered noxious weeds because of their ability to clog waterways. Federal law in the U.S. prohibits their sale in some states.
Hydrocharis morsus-ranae, Frogbit	The common name frogbit is applied to several different plants. Hydrocharis, morsus-ranae and Limbonium spongeanum the two most common and is unfortunately the object of some confusion. Hydrocharis morsus- ranae is the prettier plant, with small, white, three petaled flowers that look like miniature water poppies. Leaves are shiny and heart shaped and have a "floating sac" on the undersides. It is a great plant for the small pond and for containers because it is pretty and easy to grow. Grows in sun to part shade with a running spread, reaching up to a half inch tall. It forms buds that sink to the bottom of the pond to over winter until spring. Hardy in Zones 4-10.
Hyfroyza aristata, floating purple spike	A small floating, creeping grass of warm waters, this plant is ideal for containers and small water gardens. It also works well at the edge of the pond or as a floating cover beneath taller plants. As the plant matures, it develops a burgundy chevron in the center of each leaf, providing additional foliar interest. It is able to float because its leaf sheath becomes spongy. As it does, it takes on a reddish tan color. Its flowers are uneventful, about 2 inches tall, appearing as black or brown spikes in late summer. Grows in part shade to part sun. Hardy Zones 9-11.
Lemna, duckweed	Known as the smallest flowering plant in the world, many species make up the genus lemna, commonly called duckweed. Most duckweed's have leaves that are round or almost round. They are slight round or almost round. They are light green and less than 1/8 inch in diameter, with a single root growing from the undersides of the leaf. The do also flower, the blooms are so Minuit they defy detection by the naked eye. Duckweeds grow in sun to part shade with a running spread, quickly covering water surface. If you have a skimmer these will quickly be sucked in. Good idea to put them in a hoop with other floating water plants to keep them around with the skimmer. Duckweeds grow in sun to part shade. Hardy in Zones 3-11, they overwinter by producing buds that sink to the bottom of the pond. Fish also like to eat duckweed, and it may be have a hard time staying alive in the pond shared with koi or goldfish.
Limbonium spongeanum, frogbit	This one looks very much like the other type of frogbit. But it has shiny leaves that are oval, not heart shaped. It, too, has a floating sac on the underside of each leaf. Blossoms are not very showy, just 1/4 inch, scrizzly mops of pale cream. The plant produces shorter runners, and more of them, than the hydricharis. Grows in sun to part shade with a running spread, reaching 1/2 inch tall. Hardy Zones 4-10. Overwinters threw similar buds.
Neptunia aquatica, sensitive plant	Sensitive plant, so named for its foliage that contracts at the slightest touch, has leaflets that are opposite, growing on either side of the petiole, arranged to resemble dragonfly wings. Its flowers are yellow tufts about 1 inch wide, appearing freely throughout the summer on the running stems. The plant's main floating stem becomes stout, white, and matted as the plant matures. Growing naturally in warm regions, sensitive plant is native to South America. Although it is often sold as a floating water plant, it also grows well rooted in soil at the edge of the pond, where it reaches about 6 inches tall. Situate in sun to part shade. Hardy in Zones 9-11.