Discussion

Mizuaoi & Water Hyacinth

The main thing to know is that it has characteristics similar to water hyacinths (Pontederia crassipes), a plant called hotei aoi in Japan. Water hyacinth's come from South America, but have spread around the world since the late 1800s.

Here is another picture of mizuaoi blossoms. It can be seen that they come in clusters like the water hyacinth, but not so tightly grouped. The colors aren't always so deep a purple as in the first photo. You can see part of the mizuaoi's heart-shaped leaf below the blossoms.

Water hyacinth leaves can be seen in his photo. Note, also, the bulb-like swelling at the base of the leaf stems just above the water. That helps them float above the water.

Here is a better look at mizuaoi leaves.

Something the two plants have in common besides being water plants is that they are extremely fast growing perennials that are extremely hard to eradicate. They can rapidly choke waterways, crowding out other plants. Resulting decay can deplete oxygen in water, killing fish. They are considered to be environmentally dangerous pests, and is it illegal to sell or transport the plant in many areas.

Here is what unchecked growth by mizuaoi looks like.

Here is a similarly affected pond with water hyacinth.

Water hyacinths reproduce both by runners and by seeds. Seeds, produced in the thousands, remain viable for up to 28 years. Mats of water hyacinths can double in size in one to two weeks.

There have been attempts to find uses of the plant. Some areas use it as animal feed. Others use them in manufacturing consumer products like these disposable plates.

Artwork

Imao Keinen (1845 – 1924)

One of this shin-hanga (new prints) artist's major works was a book of kachō-ga prints titled Keinen Kachō Gafu (published in 1892 before the shin-hanga movement started). This Mizuaoi, Chinese Arrowhead, Rush & Water Rail print was one of them.