Oregon’s Own Marionberry

Beloved hybrid berry created in 1940s Oregon

By Robert Matsumura, Contributing Writer

If you’re like many Oregonians, summertime and Marionberries go hand-in-hand. From early July through August, Marionberries are harvested and begin appearing in the produce section of grocery stores, pies and a plethora of other food and drink items. But, did you know that this scrumptious berry did not even exist until the 1940s? Had you walked into a Portland diner in the 1920s and asked for a slice of Marionberry pie, you would have been met with puzzled looks.

While an urban myth circulates that the Marionberry was named for the American politician Marion Barry, the actual origin of this delectable berry traces back to the 1940s when the U.S. Department of Agriculture and Oregon State University collaborated to create a blackberry hybrid like no other. The two organizations have long worked together cross-breeding berries in an effort to produce varieties with greater flavor, fragrance and higher yields. In the Marionberry this collaboration struck pure gold.

It was USDA horticulturist George F. Waldo with the agency’s station in Corvallis, and horticulturists from Oregon State University, who were responsible for bringing us some of our state’s signature berries. One of these was the Hood Strawberry — the favored variety of Oregon berry farmers and local consumers alike. The other berry creation was the Marionberry. This partnership between USDA berry breeders and OSU horticulturists is unique — a true one-of-a-kind collaboration that has spanned over a century and exists nowhere else in the world.

Chad Finn, a USDA-ARS research geneticist who currently occupies Waldo’s previous position in Corvallis, describes Waldo’s pioneering work as, “classical plant breeding,” a process that is “always a combination of art and science.” Finn’s admiration runs deep. “One of the things that I think is lost, really, is that he created a whole crop that never existed before,” Finn explained. “That’s remarkable. We would be dead in the water without him or somebody like him.” Because much of the early testing for this new berry creation was done in Marion County, it was called the “Marionberry.”

So, what exactly is a Marionberry? The Marionberry is a cross between a Chehalem blackberry (a berry with native blackberry, loganberry and raspberry in its genetics) with an Ollalieberry (another blackberry crossbreed). All that one needs to know, though, is that it is absolutely delicious! Linda Strand of the Oregon Raspberry and Blackberry Commission describes the Marionberry as “sweeter than most other berries, but not overly so.” She shared that “in blind taste tests around the country, people always prefer it. It’s our gold standard in the industry.”

Marionberries are often marketed as being seedless, but, in fact, a seedless berry is actually impossible. Even though one detects no seeds while eating a Marionberry, there are, indeed, extremely flat, thin seeds in the berries that are coated with a gelatinous material that renders them undetectable to the tongue.

According to Bernadine Strik, an OSU professor and leader of the university’s berry research program, “Oregon continues to be known as the premier blackberry growing region in the world,” she proclaims. “It’s a fact.” And of all types of blackberries grown in Oregon, the Marionberry still reigns supreme, called by some the “Cabernet of blackberries.” The Marionberry accounts for approximately 25% of the state’s berry production, which is an impressive accomplishment for a variety that was developed over 50 years ago, and must continually compete with newer rivals bred to topple the Marionberry from its throne.

So popular was the Marionberry that in 2009 an effort was made to make it the official state berry. Many legislators supported the initiative, but ultimately the proposal was abandoned when a prominent berry producer insisted that focus on a specific berry variety might damage the sales of others. And while the Marionberry didn’t achieve official status as the state berry, the Pacific Northwest and Oregon in particular still maintain supremacy in the production of this highly prized berry.

Not only do the Willamette Valley’s cool, mild winters and warm, temperate summers create the ideal climate for berries to thrive in, but decades of Marionberry cultivation have resulted in the development of harvesting techniques specifically designed for obtaining the optimal yield. Marionberries are delicate by nature, and in order to maintain consistent flavor and texture — particularly for processed products — specialized technology is employed to ensure only ripe berries are harvested (unlike other berry types which are harvested in large batches without such care). During the compressed four-week season that commences with Independence Day, Marionberries are picked every few days with finely calibrated row machines that vibrate at designated frequencies causing only the ripe berries to detach themselves from the plants for collection.

It is this combination of ideal climate combined with specialized harvesting technology that has limited the production of Marionberries to this region. Other areas of the country lack either the climate and/or harvesting technology which are critical for successful commercial production of Marionberries. And while Marionberries are still a wildly popular treasure of summer, the cultivation of these marvels of the berry world pose a number of challenges. Since Marionberries are thorny, hand-picking is difficult (requiring specialized machinery as noted above), and they are less cold-tolerant than other varieties, which can affect variances in production volume. These are a few of the challenges horticulturists are striving to solve through selective breeding and experimentation.

If you’re wondering about the difference between Marionberries and blackberries, here’s a simple rule of thumb: Not all blackberries are Marionberries, but all Marionberries are a type of blackberry. Visually, Marionberries are more oblong, and tend to be sweeter and juicier than blackberries, and in general a bit firmer.

So, the next time you’re enjoying a slice of Marionberry pie or, perhaps, a Marionberry ice cream cone on a warm summer day, remember George F. Waldo and the many hard-working horticulturists at the USDA and Oregon State University who over the years have created this delectable true Oregon original, and are still striving to develop new delicious berries for future generations.