Are you ready to assist in haskap berry research?

Often given in Hokkaido, Japan, as a gift, the haskap berry is prized and in demand in Japan. Top, Depending on the variety, haskap berries vary in shape, size and taste.

Haskap, a subspecies of blue honeysuckle, is a delicacy as fresh fruit, in baked goods, as wine, candies and ice cream in Japan.

Dr. Maxine Thompson, retired professor emeritus from the department of horticulture at Oregon State University, is likely the only person working on an active breeding program in the United States to develop haskap varieties suitable for the American Northwest climate, and she is on the cusp of several cultivar breakthroughs. The challenge is that she needs assistance, land and financial support to take her research to the next step, where proven, high-production, and easily harvested varieties begin to show up in U-Picks and commercial berry operations.

"I really believe that these berries have a lot of potential in high-value processed products," says Thompson, who is currently running her research and breeding program on a shoestring budget in her retirement years. "The Japanese in Hokkaido have developed numerous processed products and they sell them as gift packages because they are so expensive." She adds that they have no method of mechanical harvesting, so they hand-harvest and their wage costs are high. Therefore, the industry is not growing, but they are interested in more berries.

The word haskap comes from the Ainu, who are the indigenous people of Hokkaido.

Assisting Thompson in her research is Dr. Danny Barney at the Research Extension Center at Idaho State University in Sandpoint, Idaho. He is helping evaluate Thompson’s work and grow some of her plants, but even his funding is in jeopardy. The U.S. program is a far cry from the investment being made in Canada at the University of Saskatchewan, where a significant effort has been made to breed new haskap varieties that are already reaching growers. New plant varieties filtering down to producers have even spawned a fledgling Canadian growers association.

Thompson says that haskap should not be confused with honeyberries, which are a blue honeysuckle variety from Russia that has not performed particularly well in the Northwest climate. Her varieties come directly from Hokkaido, Japan, which has a much more comparable climate to the American Northwest. Those varieties have done well because they bloom about a month later than the Russian varieties and have a better survival rate in a variable winter climate like the Northwest.

Haskap has a number of favorable traits from both a production and nutrition standpoint. As far as a commercial crop, it is frost-hardy, with blooms reported to have withstood as low as 17 degrees Fahrenheit; dormant plants have withstood temperatures as low as minus 50 degrees Fahrenheit. They are also an excellent complement to blueberry crops because the haskap crop is typically ready for harvest in May or June, earlier than some strawberries. This could help commercial operations develop additional cash flow when they could use it. It’s not known if commercial blueberry harvesters will work on haskap shrubs. That is part of the research Thompson is conducting this summer, as she has some test plants representing a number of haskap varieties in the vicinity of a blueberry crop.

On the downside, netting protection is definitely recommended because, as the first berry of the season, it is highly attractive to birds. In fact, a flock of cedar waxwings wiped out Thompson’s entire crop last year.

A fully mature haskap bush can yield 6 to 7 kilograms of fruit per year.

What’s known about the haskap varieties so far is that they have no major susceptibility to fungi or insects, although the Japanese have treated for the botrytis fungus, the celery aphid, several species of tortricids, scale insects and yellowish elongate chafer. The Russians have reported aphids as their main insect pest.

Thompson describes blue honeysuckle species as long-lived shrubs that reach 4.5 to 6 feet. Their attractive yellow flowers in early spring and bright yellow leaves in fall make them a desirable ornamental shrub, as well as a much-esteemed berry crop. Berries are dark blue with a white waxy covering similar to blueberries. The fruit shape, however, is much more variable, from round, oval, ovate, pear-shaped or jug-shaped to long and thin, depending on the variety. Mature plants can produce as much as 6 to 7 kilograms of fruit. The taste can also vary; it covers the spectrum from mild to tart. More research is required to define the specific production and attributes of species that thrive in the Northwest. Certain tart-tasting haskap berries work well in combination with blander tasting berry species because they can enhance the taste.

"I’ve got a range and I am selecting for both directions," says Thompson.

Dr. Maxine Thompson, retired professor emeritus from Oregon State University, is the only researcher actively breeding haskap bushes, to her regret.

In terms of planting environment, haskap requires a good organic mulch and must be irrigated regularly. Certain blue honeysuckle varieties are indigenous to areas with colder climates in North America, and are often found near sloughs. They are more soil pH-tolerant than blueberries, which require an acidic soil.

From a nutritional standpoint, it contains more vitamin C than an orange, ranging from 50 to 70 milligrams per 100 grams. Berries are also high in anthocyanins and phenolic compounds, which provide the health benefits derived from antioxidants. In fact, according to Thompson, the medicinal values of the fruits have long been appreciated for their therapeutic effect on cardiovascular diseases, they are known to reduce blood pressure and there are claims for curative effects for malaria and gastrointestinal diseases. That’s because variations of blue honeysuckle have been grown and harvested in areas of Japan, northern China and Russia for centuries, which has resulted in accumulated knowledge about attributes of the various subspecies. "They are known as a health-promoting food in both Japan and Russia," says Thompson. "In fact, they are in a book on medicinal plants written in Russian."

Thompson’s work so far could come to a halt once she is no longer able to continue her independent study. Right now, it’s operating on a $10,000 per year research grant, and her volunteer time.

Haskap berries are ready for picking in May or June, often before some strawberry varieties.

"Ideally, it would be nice to have some land at the department of horticulture farm, and have it set up with drip irrigation and netting like I have at my home," she says, "but I don’t know how much that would cost; it would cost a lot. Then, I need an assistant to help in the maintenance, harvesting and evaluation."

So far, no one has expressed an interest in following up with her research, even though she is already on the cusp of determining those varieties best suited for commercial production and those for home gardens.

"They make a wonderful flavor in the processed products," Thompson says. "There are all kinds of possibilities."

For more information, contact Dr. Maxine Thompson, 4017 Ag Life Sciences Bldg., Corvallis, OR 97331-7304; call 541-737-3695; or e-mail

The author is a freelance writer and frequent contributor to Moose River Media publications.