The most known and most popular is the cordata. It grows 2 to 3' tall and flowers from June to September. This fact alone makes it a very popular pond plant. And it is a very easy plant to grow. It is a native American plant that is hardy to zone 3. The foliage is dark green and on the cordata and the flower is a bright purple color.

The Giant Pickerel Rush, Pontederia lanceolata grows 3 to 4' tall. The flowers are more of a lavender-blue than purple. It is hardy to zone 8.

The Royal Pickerel grows 4 to 5' tall and the flowers are more blue than purple or lavender. It is hardy to zone 7.

The Giant White Pickerel Rush grows 3 to 4' tall but has white flowers. It is hardy to zone 8

Singapore Pink is a newer variety and has bright pink flowers and is hardy to zone 9.