Container water gardening allows you to add new plants to your landscape. A container water garden is a small-scale version of a pond. Just like a full-sized pond, a container water garden provides an environment for aquatic plants and even fish. This can be a good way to try out water gardening before investing in a full-sized pond. Any container that holds 4 gallons of water will work for a water garden. Use a small water barrel to build a container water garden.
Line your water barrel with pond liner plastic. Attach the plastic to the inside lip of the barrel with heavy-duty staples. Water barrels contain toxins that can leech into the water, and the barrels may leak along the joints. Lining a water barrel helps to hold in water and keep out toxins.
Select miniature pond plants for your container garden that will not overwhelm the space. Your plant selection should include marginals, such as miniature cattail or Louisiana iris, floating plants, such as parrot feather and water lettuce, and medium-water plants such as miniature water lilies.
Place rooted water plants in smaller clay containers or net baskets filled with equal parts sand and peat moss. Cover these containers with a layer of pea gravel and place them beneath the surface of the pond. These containers may be brought indoors during winter to prevent the plants from freezing.
Place the containers or baskets at their proper depth in the barrel. Shallow plants, such as marginals, may be kept near the surface of the barrel by propping them on top of bricks. Keep deeper plants, such as lilies, near the bottom of the barrel.
Add small fish to eat the mosquitoes in the barrel or feed off of the plants. As a general rule, avoid koi or goldfish. Instead add guppies or minnows. Add 1 inch of fish per square foot of water surface. Fish should be added 4 to 5 weeks after plants are established.