Illustrations of Morning Glories

The Japanese morning glory (Ipomoea nil) and related plants
There are various varieties of the Japanese morning glory. Middle-flowered morning glories, those with diameters of more than 10 cm, and large-flowered morning glories (those with diameters of more than 15 cm) are very familiar in Japan. These varieties have been produced and improved for a long time.
The base (original) species of the above morning glories seems to have been a blue flower with a diameter of 5 to 6 cm, and it probably resembled the flowers shown in 4-6 on page 25.
1 Blue dawn flower, Ipomoea indica (Noasagao in Japanese) This variety grows wildly in Okinawa, Kagoshima, the southern coast of the Kii peninsula and the Shikoku area. The flower is a bluish violet color, and the flower diameter is about 8 cm.

2 Common morning glory, Ipomoea purpurea (Marubaasagao in Japanese) This one is native to tropical South and Central America. And it has many gardening varieties. The leaf is round, and the flower diameter is 5 to 6 cm.

3 Ivyleaf morning glory, Ipomoea hederacea (Amerikaasagao in Japanese) The distinguishing characteristic of this one is the constricted (narrow) part in the leaf. The flower diameter is about 3 cm. The above species are very close to the morning glory (Ipomoea nil). They are all in the same section, called Pharbitis.