Water Gardening

Mary Ann Ryan
Adams County Master Gardener

(3/1) What do you think of when you hear "water gardening?" As it turns out, many folks have different visions of what a water garden is, or looks like. Water gardens can be something as simple as a birdbath, as challenging as a fish pond, as big as a farm pond, or as structural as a fountain.

When considering a water garden, first it must be determined what the purpose of the garden is. For instance, maybe a focal point is needed; or possibly someone just wants the serenity of the water trickling over rocks. Maybe the excitement of growing plants that like it wet is the reason for a water feature. The reason will direct what kind and size of garden you choose.

When choosing the direction of the water garden, size and scale must also be a consideration, as well as the maintenance involved in the finished project. All water features need winterizing; either dumping water out of a birdbath and turning the bowl upside down, or putting a heater in the bowl to keep it from freezing. Most water features require electricity and access to water. If neither of those is available at the selected location, then adaptations will need to be made. Garden ponds require full sun. Plants are necessary for a balanced water pond, and most water plants are sun loving.

Letís start from the beginning. Assuming your water feature is a garden pond, thereís lots of options. Garden ponds can be constructed with flexible liners or pre-formed liners. Either requires a flat surface, and sand or quarry waste that goes under the liner. (There are many resources available that speak to the depth of the foundation and sides of garden ponds.) Itís very important that no shortcuts are taken in the construction of the pond. Rocks can puncture any liner. After the hole is dug, the sand/quarry waste is installed.

The depth of the pond will be determined based upon on whether the pond will hold fish or plants, or both. For fish to winter over in our area, the recommendation is a minimum depth of 2.5 feet, 3 feet ideally. When digging the pond or choosing a pre-formed liner, consider shelving along the edges. This will allow for a variety of plants that like shallow water, but not submersion.

After a pond is installed, the fun part begins Ė choosing plants! For a pond to function correctly, a good balance of plant and fish life is important. In order for fish to flourish, the surface of the water must be shaded. However, the plants themselves mostly need full sun to grow, although there are some exceptions.

When growing plants in the pond, the best choice is to plant them in pots and submerse the potted plant in the water. This becomes much easier to maintain and control the size and location of the plants within the water pond. The soil used is just regular garden soil; no need for anything special. The container can be any nursery pot that will hold the root system. There are products that are made just for water plants, containers and soil, but these are unnecessary.

Provided below is a list of shallow-loving plants. These plants are good choices to place along the shelves that are constructed within the pond.

Cardinal Flower Ė Lobelia cardinalis. This fantastic plant is native to our area. Found naturally along stream banks and boggy areas, this plant gets red flower spikes that can reach to 4 feet high. It typically blooms in mid-summer and the hummingbirds love it.

Cannas, although tender, work great in a water garden. These plants can be found with red, yellow, pink or peach flowers, blooming in August Ė September. The foliage can be quite striking as there are variegated varieties available in addition to green leafed varieties. These plants would need to come out of the pond and the tubers stored in a cool, dry location through the winter until the water warms up in the spring. Reaching about 5í in height with flowers, this is a plant worth considering on the shelves of your garden.

Pickerel weed, Pontederia cordata, is another native plant that grows in shallow, mucky areas. Next to the cardinal flower, this is probably one of my favorite wetland plants. Grow in a container, as you would all other water plants. It gets a blue flower spike in June, reaching about 2í Ė 3í. It has nice foliage spring through fall.

A group of plants that may be at the top of our list is the water iris. There are two species that are typically associated with water gardens. One is Iris versicolor. This is a blue iris, blooming typically in May. Iris versicolor is a native perennial, found in wet sites along ponds and streams. This plant is a great addition to any water garden. It doesnít spread very quickly, so dividing it is probably an every two or three year chore. However, Iris pseudacorus is a yellow iris, and spreads quite rapidly, some may even call it invasive. This is not one to ever plant directly in the soil, but in a container that can be managed on a yearly basis. It will grow quickly. Both irises will grow as much as 2í tall, sometimes reaching 3 feet.

Sweet flag, Acorus calamus, resembles the iris in foliage. Sword-like leaves will often be mistaken for the iris. However, when in flower, there is no mistake. This plantís flowers are inconspicuous by many standards, growing a hidden green colored spike in among the foliage. Some may say that this plant has a sweet fragrance as you brush against the foliage, although I have never happened upon this pleasant fragrance.

Other types of plants needed for a water garden include the water lily type plants. These are plants that should be planted in pots and sunk down to the bottom of your garden pond. Water needs to at the very minimum, cover the container.

Many types of lilies are available for the home water garden. The tropical water lilies are those that must be treated as you would a canna. Lift the tubers in the fall, cut off any foliage that is left, and store it in a cool, dry location. Or treat it as an annual plant Ė one season. Tropical lilies come in many shades of pinks, purples, and other colors.

The hardy water lilies, however, are exclusively white or yellow. But the good thing about these plants is that they can be cut back and wintered right in the pond, provided itís at least 2.5 feet deep.

Lotus, Nelumbo nucifera, is a beautiful plant, although aggressive. This big guy needs to be grown in a large container and divided yearly to keep it under control. The flower arises above the water on a sturdy stem, in shades of pink, white, red and others. It is a very colorful flower and majestic plant in the water garden. Any of these lilies provide water surface shade for the fish in the pond. They keep the water cool, and are great for color in the garden.

Floaters often refers to those plants that hang out on the surface of the water. These roots do not need soil in order for the plant to survive. Some such plants are the water lettuce and water hyacinth. Both of these plants are annuals in this part of the county, however, in warmer climates where there is no freezing temperatures, they will survive from season to season.

The water hyacinth has a purple flower in the summer and rounded leaves. It will add some texture to the surface and provide quick shade as they multiply quite quickly. The water hyacinth is invasive in warmer climates, so if moving south, donít ask to buy a water hyacinth!

The water lettuce does not produce flowers, but has rosettes of green leaves that float, adding texture to the garden.

Some things to remember: water gardens work well when there is a balance of fish and plant life. Bubblers, fountains and falls will add oxygen to your garden, keeping it healthy as well. When maintaining a water garden, be sure to manage plants properly. Keeping them in containers and dividing them regularly will help keep the liner from weakening due to the roots of plants and maintain a healthy balance in the pond.

Donít take shortcuts when installing any pond or water feature. Level ground and a proper base is important in the longevity of the water feature.

When deciding on a project like a water feature, do the research. These can be the most beautiful part of a garden when managed properly.

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