Water Gardening OH 49
Leonard Perry, Extension Professor
Water adds beauty and tranquility to any garden. A water garden can be created in almost any sunny location by
digging a small pond or pool. Tub gardens, on a smaller scale, can yield beauty with an 18- to 24-inch deep tub. To
give a more natural effect sink, the tub in the ground up to its rim. Fill half full with good rich topsoil. Then, add about 1
inch of clean sand or small stones. Fill the tub with water and plant lilies in the tub, with the rim of the pot at the top of
the topsoil. You can use a wooden whiskey barrel or perhaps a large ceramic pot that will hold at least 4 gallons of
water to grow water plants on a patio or deck.
Water gardens are very easy to care for once established. Removing dead leaves and controlling the growth of algae is
often all the attention required. A new pool is likely to grow algae even with the recommended number of plants. The
conditions should clear once a balance is achieved, with only temporary relapses to green water caused by warmer
weather and higher light intensity in spring and early summer. Don't change the water as this will further destroy the
environmental balance. Algae can be controlled by adding more aquatic plants, tadpoles, or snails. If adding fish or
snails, "oxygenating plants" such as Arrowhead (Saggitaria) should be used to add oxygen to the water. Blanket
weed algae can be removed with a notched stick or rough wood, poked into the mass, twisted, and drawn to the side
to remove it. A filtration system can help remove the free-floating type algae.
Some of the many possible water plants follow:
Water Lilies (Nymphaea): These are hearty feeders and need good rich soil. If the lily doesn't have leaf growth on
it, set the basket on bricks or stones so about six inches of water covers the top of the pot so the lily can get some sun.
As it leafs out and grows, lower the lily plant to deeper water; 36 inches of water above the crown of the lily plant is
enough to induce free flowering and safeguard the roots in the winter. Water lilies should bloom from the end of May
to frost, from mid-morning until dusk.
Nymphaea 'Attraction': This cultivar with deep red blooms is one of many hybrids available. It is slightly fragrant
with nice foliage. This lily will bloom freely in water up to three feet deep and spreads 6 to 12 square feet. 'Attraction'
is easily adaptable, making it an excellent plant for beginners.
Nymphaea odorata 'Sulphure': This water lily has a yellow flower and spreads 1 to 12 square feet. It is good for a
small pool, or tub, and holds its flowers slightly above the water surface. The leaves are lightly mottled and it is a
Water lilies that are in whiskey barrels or small containers will not survive Vermont winters. These can be moved to a
garage or cellar where temperatures don't get below 25 degrees F. Don't let them freeze or thaw. A connected garage
is good because it gains heat from the house. If you don't want to move the whiskey barrel, remove the mesh basket,
clean off the leaves and old foliage and let drain overnight. Place the containers in a plastic bag with holes poked in it.
This should be placed in a cool area (32 to 35 degrees F is good)--don't freeze it!
Pickerel weed (Pontederia cordata): Pickerel weed can grow 1 1/2 to 2 feet tall. An excellent blue-flowering plant
with heart-shaped, smooth, shiny leaves on long stems, it flowers from June to October. Plant it at the edge of the
pond with roots covered with water. Plant in groups for effective color. For winter, if the plant is in a pot, clean off old
leaves and heel in. Mulch with leaves or put deeper in the pond.
Cattails (Typha angustifolia): This plant has spiked brown flower heads, and the leaves are flat, grassy foliage 2 to
5 feet tall. Plant in shallow water along a pond or marsh edge. The leaves are narrower than the common cattail.
Dwarf Cattail (Typha minima): This small cattail grows 1 to 1 1/2 feet tall with tiny, purplish-brown pokerheads in
Water-Lettuce (Pistia stratiotes): Not a lettuce at all, this shade-tolerant plant has fluted blue-green leaves and is a
Water-Hyacinth (Eichhornia crassipes): With blooms similar to its namesake, the bulbous hyacinth, it blooms best
when confined to a small area.
Sources: check online search engines, or local full service garden centers
(Adapted from Hamlen's Garden Center, Box 1400, Swanton-St. Albans Road, Swanton, Vermont 05488-9719)
Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the United States Department of Agriculture. Lawrence Forcier, Director, UVM Extension System, Burlington, Vermont. University of Vermont Extension System and U.S. Department of Agriculture cooperating, offer education and employment to everyone, without regard to race, color, national origin, sex, religion, age, disability, political beliefs, and marital or familial status.
Last reviewed 2003