What Is Loquat Leaf? Loquat leaf comes from the Loquat tree and helps to produce the Loquat fruit known as Eriobotrya japonica. It comes from the rose family and is sometimes called the Japanese plum leaf. The Loquat tree is a moderately sized tree and can grow up to thirty feet. The Loquat leaves are evergreen and are five to twelve inches long and three to four inches wide. These beautiful leaves are glossed and dark-green. Loquat leaves originate in the southeastern part of China and perhaps southern Japan, although some believe it was brought to Japan long ago by Chinese travelers. Legend has it that it has been grown in Japan for one thousand years.