Meet the World's Smallest Fruit

The duckweed with the translucent rounded top is Asian watermeal; the rest is another duckweed species, Northern watermeal.
The duckweed with the translucent rounded top is Asian watermeal; the rest is another duckweed species, Northern watermeal. | Andrey Zharkikh, Flickr // CC by-2.0

by Aliya Whiteley

It's easy to be impressed by big things. The blue whale, the African elephant, and the giant sequoia are all easy to spot, if you ever get lucky enough to see them in person. But sometimes the smaller things—particularly the things that you can barely see with the naked eye—get overlooked.

Even so, there can be no doubt that the Wolffia globosa is an impressive plant, even if it would look like a tiny speck in the palm of your hand. Better known as Asian watermeal, it's the world's smallest flowering plant, less than one-third of an inch wide at its largest.

A kind of duckweed, Asian watermeal grows quickly, spreading across the surfaces of bodies of water at an incredible rate, floating without needing roots, stems, or leaves to survive. Mainly it reproduces asexually, but very occasionally it flowers, and from the flowers comes the smallest fruit in the world, known as an utricle [PDF].

You'd be hard pressed to feel full on a meal of utricles, given how tiny they are, but they are edible, as is the whole plant (although separating the fruit from the plant might be a bit of a challenge). In fact, duckweeds are already cultivated in Southeast Asia for food and are high in protein; duckweed has been vaunted as a new and plentiful food source for us all, given how quickly it multiplies. Apparently, it tastes a little like watercress.

This mighty microplant is also being investigated as a possible energy source. As a biofuel, it would be carbon neutral, as it removes carbon dioxide from the atmosphere. Additionally, it could be used to purify water, balancing levels of phosphorus and nitrogen; it can also pull both arsenic and cadmium from the environment.

To cap it all, Wolffia has been investigated as a possible food source for long-term space travel. For a speck of a plant that's easy to miss, it has some big potential.

If you'd like to give it a taste, here's a recipe from Recipes Thai Food for a watermeal omelette.