As American as Walt Whitman, the American Revolution and berry pie, the Marion blackberry, or “Marionberry” as it is known by consumers and marketers, is a distinctly American berry with worldwide appeal. A cross between the Chehalem and Olallieberry blackberries, the Marionberry captures the best attributes of both berries and yields an aromatic bouquet and an intense blackberry flavor for which it has become known. This premium quality flavor, described by tasters as “earthy cabernet”and
“sweet with notes of tartness”, makes the Marionberry a superb choice for canning, freezing, pies, jams, jellies and ice creams and has earned the Marionberry an outstanding reputation worldwide. Since the Marion is considered of premium quality, it is usually sold under the Marionberry name, whereas other blackberry varieties are sold under a generic “blackberry” label. Marionberries are sold to the consumer fresh during harvest season (typically July 10-August 10), and frozen in 16 ounce poly bags, during the rest of the year. 

The Marionberry is the most widely planted blackberry variety in the world and is grown exclusively in Oregon.  Here, the spring rains and sandy soils of the lush Willamette Valley have increased production to 26 million pounds since 1956 when the Marionberry was first introduced to the American consumer. In fact, the Marionberry was developed here among the fields of Marion County and from this birthplace the Marionberry hails its name.  Marion County itself is named in honor of the daring “Swamp Fox” hero of the American Revolution, General Francis Marion. 

The memorable flavor of Marionberry’s ancestors impressed Walt Whitman enough to write that blackberries “adorned heaven”. It is the intense blackberry flavor of the Marionberry, coupled with an enticing aroma and the perfect balance of tart and sweet flavors, which have this particular blackberry variety fast becoming an American favorite. “(The Marionberry) has a true ‘berry’ flavor.” 

This article courtesy of the following folks:
http://www.oregon-berries.com/