Aquatic plants are an important part of the water garden. They provide beauty and naturalization with a huge array of plant choices. Most importantly, they help balance the pond’s ecosystem and provide valuable biological filtration that removes nitrogen, ammonia, nitrates, and other minerals from pond water. These excess nutrients are often the cause of unsightly water conditions. The end result helps to minimize pond maintenance, leaving more time to enjoy your pond. Without aquatic plants, your pond would not be able to function as a complete ecosystem. Pond plants can be classified into a few main categories: waterlilies, marginal plants, floating plants, and submerged. Plants can also be put into two basic types known as “tropical” and “hardy.” Hardy plants will over-winter in colder climates and tropical plants are more suited to warmer climates, although tropical plants are often used as annuals in colder climate zones.