Water Garden Plants

The selection of Water Garden Plants is as varied as the colors of Koi. Most ponders will choose water garden plants not only for the visual effects but for the benefits they have for your water and fish. You should look for plants that blend in with the design of your water feature and the rest of your yard. Whether your design is formal or informal will affect the way you use plants.

There are a number of practical uses of plants that you should consider for around your water garden: for reducing wind, discouraging predators, framing view, and defining paths. You will certainly want to take advantage of your ponds ability to reflect plants with colorful foliage and dramatic shapes, and to situate fragrant plants near benches or other stopping places.

To make your water garden an integral part of your landscape, you may want to choose flowers with colors that echo those elsewhere in your garden. Light affects how we see color. In a bright sunny garden, hot colors such as reds, oranges, and bright yellows stand out. If your garden is somewhat shady or if you are designing an evening garden cool blues, pinks, and especially whites will seem to glow in the fading light and create a tranquil atmosphere.

Submerged Plants or Oxygenators

Submerged plants are those that grow below the water surface. Also called oxygenators, these plants act as natural filters to help keep your pond in chemical and biological balance, making it more hospitable for fish and less inviting to algae.

A healthy water garden is a living organism, and submerged plants are its lungs. Catalogs often refer to submerged aquatic plants as “oxygenators,” because during the day they produce oxygen that helps support your fish.

Submerged plants also function as kidneys and biological filters by removing mineral salts and fish wastes that feed unsightly algae. Place a few weeks before you introduce any fish, to allow them time to get established and get your waters chemical balance on an even keel.

Planting Oxygenators

Submerged plants are among the least demanding of garden residents. Because they obtain their nutrients from the water, you can plant them in sand or gravel and they will never need fertilizing.

Tip: Do not ever plant them in rich soil, manures, or composts, as nutrients will leach out of these and upset the ecology of your pond. In fact, oxygenators do not even need containers. You can band them in bundles of a half dozen plants and weight them down on the bottom of the pond with a rock.

If you are using containers, fill them with sand almost to the top. Then use your finger to poke each stem an inch or two into the sand. Plant one stem for roughly each inch of pot diameter. Top the sand with clean gravel, which will help hold sand and plants in place, and add some water to help displace air bubbles.

If you have Koi or other ravenous feeders, you may want to protect your plants with mesh, which you can buy from aquatic suppliers.

Lower the post slowly into your pond. There should be 1 to 2 feet of water over the roots of the plants. If you have a deeper pond, set the containerized plants on blocks to ensure that they get enough sun. They will tolerate semishade, but they will die if sun is blocked by too many floating plants or by algae. Keep the pots well away from your pump; most water garden plants do not like much agitation.

Once the plants have grown about a foot long, you can cut off half their length and reroot the tops in new pots.

Description: Native to coastal areas of southern and coastal areas of southern and central North America, water hyssop has a stiff, round stem 2 feet long that is covered with fine hairs. Egg-shaped leaves are about an inch long and hairy underneath. Light blue tubular flowers about ½ inch long appear about the water in the leaf axils (where leaves are attached to the stem).

Description: This plant is native to ponds and streams from Michigan to Texas and south to Florida. Underwater, its leaves are feathers, in a fan shape 1 ½ inches across. Leaves that grow about the water are linear, pointed, and ¾ inch long. The tiny flowers are usually white with yellow spots, although they are sometimes purple.

Description: Hornwort develops stems 1 to 2 feet long, clothed in whorls of forked leaves, that remain completely underwater. Like some other aquatic plants, it reproduces from turions, buds that drop to the pond bottom in winter. You can pot up these turions when they start to grow in spring.

Like submerged plants, floaters play an important role in creating a healthy natural balance for your water garden. The leaves of these plants float on the surface and shade the water, making it less hospitable for algae, cooling the water for fish, and giving fish a place to hide and to lay their eggs while spawning. You may decide not to include floating plants in your water garden, especially if it has a fountain. A fountain or waterfall that churns the water of a small pond will create too much commotion for them.

Most floating plants prefer full sun but will tolerate at least partial shade. Water lilies, as a rule, require at least six hours of sun a day to bloom. Lotuses are less particular about the amount of sun they receive than they are about temperature. They will bloom in partial shade, as long as they have a sufficient stretch of warm weather. Other options for flowers in partial shade include water hawthorn and pond lilies.

Description: Tropical gardeners can try this South African perennial with 8-inch elongated oval leaves. Heavily scented flowers, which bloom in both spring and fall, are held on a double spike; their purple-brown anthers look like freckles on the rows of white petals. Give water hawthorn a container 1 foot across and start it about 4 inches below the surface of the water, lowering it 1 to 3 feet.

Grows similar to a waterlily, but is smaller, with long, narrow floating leaves. Abundant blooms very early in the spring, and flowers smell like vanilla. Tends to go dormant in hot summer weather, but excellent for spring and fall, before and after waterlilies are at their peak. In mild climates they usually bloom year round; in hot climates, they bloom in fall, winter and spring.

Description: Often called by the more charming name of fairy moss, this tiny aquatic fern with inch-long frond floats freely on the water surface, each plant about its own little root. The dainty green snowflakes turn burgundy in autumn or in strong sunlight. This plant can easily become invasive. It can be useful if you need quick cover for a new pond and are willing to thin regularly.

Description: This is one of the most beautiful yet one of the most noxious water garden plants. One of the worst pest plants in California, Florida, Georgia, and Louisiana, it can not be shipped across state lines anywhere. Its shiny round leaves bob in the water, supported by buoyant stems. The free-floating plants are topped by 6-inch spikes of exotic looking lilac flowers. Be prepared: this rampant beauty can take over your water garden if you do not thin it regularly.

Description: These appealing plants are technically ferns, but as their common name hints, they look like four leaf clovers or shamrocks. The most colorful is M. mutica, from Australia; its quartet of 3-inch leaves has two shades of green separated by a dark band. Water clovers can be grown in up to 12 inches of water, in which case their leaves will float. They can also be grown as marginal plants.

Marginal, or shallow-water plants occur naturally along the edges of ponds and streams and usually like water over their roots at least part of the growing season. These are the one to plant just inside the margin of your water garden. If your pool or pond does not have built-in planters or plant shelves, you will need to raise the plants containers on blocks to the depth where they grow best. Generally 2-gallon containers will do for all but the largest and smallest plants. Except for the rampant spreaders, marginals make excellent plants for tub or container gardens. Some species also thrive in garden beds if the soil is well amended with organic matter and kept moist.

Beloved by florists this 2 to 3 foot tall bulbous plant from Africa can be grown as a marginal aquatic in warm climates, although it is almost too beautiful to look at home in an informal pond.

Its shiny leaves are arrow shaped. The cup-shaped fragrant white flower (spathe) surrounds a club, or spadix.

Grow calla lilies in a container of heavy soil under a foot of water. They can also be grown in garden beds; they tolerate a wide range of soils provided the soil is moist or they get regular watering.

Description: Every water garden deserves at least one elephant-leaved perennial, even though most can be challenging. Cultivated as a root vegetable in Southeast Asia, taro has 2-foot arrow shaped leaves on 3-foot stalks. Look for the cultivar “Fontanesii”, which has violet stalks and leaves that glow with dark red veins and margins. All like high humidity and filtered sun and can be planted 12 inched under water. In Zone 8 and north, store the tuber (dry) over winter in a place where they will not freeze.

Description: Also sold as E. palustris this plant also goes by the name of fiber-optic plant (as do a couple of completely different plants with a similar shape). Spike rush occurs naturally over much of the US and grow a foot high, producing a quill of little brown tufts. It likes only 2 to 4 inches of water.

Description: Many people consider these the most beautiful of irises. These plants have been bred over centuries so that their standards have all but disappeared, but the almost horizontal falls are huge and often double. This makes them look somewhat flat, best viewed from above. The many selections, 2 to 3 feet tall and in almost every color but green, frequently bear Japanese names. They can grow in an inch of standing water and should not be allowed to dry out during the growing season.

A pond stuck in the middle of a vast expanse of lawn may look artificial and barren. Add some perennial borders or use shrubs to define a pond side seating area. Larger shrubs and trees can serve as a pleasant backdrop to frame the pond, or they can mask views of property fences or a neighbors house. Remember that plantings need to be in scale with the pond and the rest of your yard. Clipped evergreen will only look good next to the most formal pool; a mix of plants if best for an informal pond, particularly a natural water garden, look as though it belongs in its setting is to surround it with plants that occur near ponds in nature. The plants described here in this section like moisture, but they also need soil that drains well. In their natural setting, you would find them on the banks above a stream or a pond, not right at the waters edge.

Although there are many members of the iris family, they are not all appropriate to grow in water gardens. The Louisiana iris thrives in wet conditions. Bearded irises, on the other hand, grow best in well-drained soil. Plant them in a sunny location, with their rhizomes exposed. Bearded irises produce the most flowers when the top surface of the rhizomes bake in the sun.

Description: Jack is the flower (a tiny knob called the spadix) and the pulpit is the hooded spathe that surrounds him. The spathe is green, sometimes streaked with dark purple, and about 5 inches long; the spadix gives way to a stalk of bright scarlet berries. Either flower or berry is a delightful surprise to fine in eastern woodlands. The leaves, which follow the “flowers,” have three parts and reach 6 to 24 inches tall. Give this plant a cool, shady place with moist but well-drained soil.

Description: Goatsbeard grows 4 to 6 feet tall and in rich soil can spread 6 feet, but it is surprisingly delicate for such a large plant. Its five-part leaves are toothed and ferny, and in late spring plants develop flowing, creamy white “beards.” Give gotasbeard afternoon shade if you live south of Zone 5.

Description: Like other milkweeds, this has tough stems, a lot of branches which make it almost shrub like, and narrow elliptical leaves. Plants are topped by a flat cluster of small flowers, each purple-pink with paler little upright “horns” and slightly fragrant. ‘Ice Ballet’, developed as a long-lasting cut flower, offers white blooms. Flowers give way to spiky pods that pop open to release dark brown seeds on silky threads. Despite its common name, swamp milkweed can grow in fairly dry soil. Milkweeds are slow to emerge in spring.

To Learn About the Lotus Flower for Your Pond Click Here!

Reference: Complete Home Gardening by: Miranda Smith

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