The Question:

What's the world's smallest flower?

The Answer:

The smallest known flowering plants are in the genus Wolffia, which float on the surface of quiet streams and ponds. The entire plant—flower and all—is less than a millimeter long. A bouquet of a dozen could fit on the head of a pin.

For more on this, and other interesting facts about the plant world, see our Plant Hall of Fame.

—The Fact Monster