Water Gardening

Flower & Garden Magazine, May, 2000 by Leslie Garisto Pfaff

Start small with an aquatic container garden.

Nothing seems to engage the senses, or enhance the landscape, like water. If you've ever dreamed of a pond of your own but were daunted by the expense and labor involved in its installation, consider starting small with an aquatic container garden. The only absolute requirements are a sunny, level spot, a watertight container and an adventurous spirit.

For gardeners with limited space and/or time, the Patio Jungle is an ideal jumping-off point; it's a free-standing container garden with a decidedly tropical feel. Or, with just a little extra work, you can install the Sunken Fish Pond. Both projects are easy to assemble (each can be completed in well under four hours) and a snap to maintain.

CREATING AN ECO-SYSTEM

Neither of these small ponds requires a filter; instead, they rely on nature to keep the water clean through a balance of flora (aquatic plants) and fauna (fish). To achieve this balance, you'll need to include oxygenators (plants whose root systems actually add oxygen to the water) and floating plants, which keep the growth of algae in check by shading the surface. Fish are an essential element in both gardens, feeding on the mosquito eggs and larvae that would otherwise collect in standing water.

Most aquatic plants require relatively warm water, so you'll need to schedule your installation for a time when the air temperature in your area has reached a reliable 70 degrees. Before adding fish or plants, let the water warm and dechlorinate for at least 24 hours.

PLANTING BASICS

Because space in both of these gardens is limited, you'll be potting up most of your plants before sinking them in the overall container. For this you'll need sturdy plastic or terra-cotta pots (see individual projects for sizes) and topsoil. Don't use commercial potting soil, which is too light for aquatic planting. Pot up aquatics the way you would any plant, adding about a teaspoon of 5-10-5 granular fertilizer to the soil in each pot before planting. It's a good idea to mulch each plant with an inch or so of aquarium gravel to keep soil from muddying the water. Then, ease the pots into the water, tilting them at a slight angle to allow air to escape. Oxygenators, such as parrot's feather, can simply be floated in the pond. To make sure that the roots stay submerged, tie them gently with a piece of string that has been weighted with a stone.

POND MAINTENANCE

Once your water garden is up and growing, it will require very little in the way of maintenance. The most crucial job is to top off any water lost to evaporation (let it warm for a few hours in a bucket before adding it to the pond) and to remove any spent flowers or brown foliage. If you like, you can add fertilizer tabs monthly (available from aquatic nurseries and mail-order sources), but your garden will probably thrive without them. The only time you'll have to do any real work is at season's end, when your plants and fish will need to come indoors for the winter. Most aquatic plants can overwinter in a state of semi-dormancy; just keep them in a cool (not freezing), dark room and water them only enough to keep the soil from drying out. Fish can spend the winter in a modest-sized tank and then make the trip outdoors again come late spring.

PATIO JUNGLE

Once out of favor, cannas are making a big comeback. Their vividly-striped foliage and boldly-colored flowers add rain forest drama to this patio pond, which also includes delicate water snowflake, a brightly-hued water lily, ferny parrot's feather (an oxygenator) and free-floating fairy moss.

You'll need: A free-standing container at least 16 inches deep and 20 inches wide (available from aquatic nurseries); 6 to 12 bricks; 3 8-inch pots and 1 12-inch pot; topsoil; 5-10-5 granular fertilizer; aquarium pebbles; 2 cannas (consider yellow-flowered C. 'Ra,' salmon-pink 'Erebus' or the dramatic scarlet 'Endeavor'); one white-water snowflake (Nymphoides cristata); one small hardy water lily (such as 'Gloriosa' with its dramatic scarlet blooms or 'Indiana' whose flowers change over the course of several days from salmon pink to orange-red); one small bunch parrot's feather (Myriophyllum aquaticum); and two small goldfish.

Set the container in a spot where it will receive at least six hours full sun daily (you'll be hard-pressed to move it once it's filled with water). Using a garden hose, fill it about four or five inches from the brim and let the water stand for at least 24 hours. While you're waiting, plot out your garden design, keeping in mind that the taller cannas should sit either at the back of the container or at the sides. When you're ready to plant, pot up all the plants but the parrot's feather and fairy moss, using the 12-inch pot for the water lily. The lily can be set at the bottom of the container, but set the other potted plants on top of stacked bricks so that their crowns are two to four inches below the water's surface. Drop in the parrot's feather and fairy moss and release the fish.