An agricultural cooperative in Kagawa Prefecture began shipments Thursday of inedible cubical watermelons.

The Zentsuji branch of the National Federation of Agricultural Cooperative Associations (Zen-Noh) will ship about 700 watermelons, grown in 19-cm glass cubes, this year to the domestic and international market, including Hong Kong and Canada.

The watermelons, a specialty of the Zentsuji cooperative, fetch around 10,000 yen each wholesale and are only for exhibition. Co-op officials say the fruit is unfit for human consumption.

"It's quite hard to grow them, but it's pretty easy to pack them since they don't roll," said Noriko Matsumoto, 45, one of the growers.