Clementines - U of I Extension

News Release


This article was originally published on December 1, 2007 and expired on February 28, 2008. It is provided here for archival purposes and may contain dated information.

Winter is the season for citrus and one popular example is Clementine, said a University of Illinois Extension horticulture educator.

"But what exactly is Clementine?" said Jennifer Schultz Nelson. "That question has sparked a lot of debate. I always thought Clementines were the same as mandarin oranges. But they aren't."

Any inquiry into the heritage of citrus fruits turns up a family tree originating in South and Indo-China and it is a complicated family tree, she noted.

"Clementines are part of a group known as mandarins, but they are not the same canned fruits so often used in salads and desserts. Most canned mandarins are technically Satsumas, originally from Japan. Another term for mandarins is tangerines," she said.

A French missionary in Algiers, Father Clement Rodier, developed the Clementine in 1902 from a cross between a tangerine and the Seville, or bitter, orange.

"The resulting fruit became very popular because not only were they very easy to peel, and delectably sweet, they were also seedless," she said. "Their popularity continues to increase today. U.S. consumption of Clementines has risen from 33 million pounds in 1994-95 to 119 million pounds in 2002-03."

The major producers of Clementines have been Spain and Morocco because of their hot, arid environments--a requirement for Clementine trees. Management of the orchards is quite intense and most of the work is still done by hand. Both countries have laws designed to maintain high quality in their Clementine harvests.

"The laws revolve around placement of viable pollen sources for Clementines," said Schultz Nelson. "Clementines have no seeds because they cannot self-pollinate, and many other Clementine and citrus pollens cannot pollinate their flowers either.

"However, there are many citrus pollens that will pollinate and produce seed in Clementine fruit, and these laws limit where or if they can be planted where Clementines are grown."

This cross-pollination issue is one factor limiting Clementine production in the United States, especially California.

"Though citrus is also grown in the hot climates of Texas and Florida, both are far too humid for Clementine production," she said. "California, on the other hand, has a great climate but there are far too many other citrus varieties grown there that contaminate the Clementines and result in a very seedy, low-quality fruit.

"Researchers are investigating ways to avoid this problem so that the United States can produce more of this highly desirable citrus fruit."

Source: Jennifer Nelson (Schultz), Extension Educator, Horticulture,

Pull date: February 28, 2008