Ohio State University researchers are in the middle of a three-year project to find blackberries better suited to the state's colder growing conditions.

Cold hardiness is the major hurdle facing Ohio blackberry growers, according to a news release.

"If the region experiences a mild winter, such as this winter, the plants will come through winter fine and produce a good crop," Gary Gao, Extension specialist and associate professor of small fruit, said in the release. "But if the winter is too cold, as are many Ohio winters, the harsh weather can cause severe injuries to blackberry crops."

Gao and colleagues are comparing the cold hardiness of four Polish varieties to three standard varieties.

They also are testing different production methods, such as high tunnels and rotatable cross-arm trellises.

Although blackberries are more challenging to grow, the return on investment is greater than some other crops.

A grower, for example, who harvests 2,000 pounds per acre may gross $4,600 per acre, according to the release.

And yields can be much greater.

Gao harvested 9,000 pounds per acre from plots of the Chester variety at the university's research facility in Piketon.

Triple Crown, on the other hand, can yield 9,000 pounds per acre one year and hardly anything the next.

Blackberries also are easier to grow than blueberries, according to the release.