Wolffia

These plants are the smallest plants in the world. They look like green grains floating in the water. The most common is W. arrhiza, Water Meal or Rootless Duckweed. It is native to Africa, Brazil, Western Asia and Europe. This plant isn't grown in the water garden purposely, but can sometimes be found in portions of other aquatic plants. This plant can become very troublesome in natural ponds; turning the water bright green.

Pot Cultivation

These plants float on the water's surface.

Propagation

These plants multiply without any help.