These plants float freely on the water surface with their roots hanging below. They do not need to be planted in any way and can simply be thrown in. As with oxygenating plants, they can help to combat algae and blanketweed, as they absorb nutrients from the water and provide shade, leaving less food and light for algae to grow. Additionally, their roots provide habitats and cover for certain pond invertebrates.
In recent years, due to concerns about the spread of invasive species, there has been a move away from exotic floating plants towards native varieties. British-grown floating plants are generally available only from late spring through to early autumn - during the winter they die back to short lengths or small structures know as turions (winter buds).