Their skin is thin and sensitive. They’re easily bruised. And their season—six to seven weeks, if we’re lucky—is more fleeting than summer itself. That short harvest time and extreme susceptibility to wind and rain and temperatures either too hot or too cold are just a couple of reasons why Rainier cherries are so special.

These spectacular stone fruits are prized for their sweetness and color. Distinctive and delicate, Rainiers—the color of a buttercup tinged with a pleasing pink to bright red blush—are little gems.

“The appeal of those contrasting colors is what makes them stand out on the tree and in the retail market. It’s just a good combination,” says WSU horticulturist and cherry expert Matthew Whiting (’01 PhD). He calls Rainiers “tree candy.”

Their flesh—creamy, yellow, firm, gently floral, exceptionally sweet—is made up of nearly one-fifth sugar, or anywhere from 17 to 23 percent. “The Rainier is a wonderful-tasting fruit,” Whiting says. “With such high sugars and typically very low acidity, it truly is like eating a piece of candy, except it’s much better for you.”

Customers have been willing to pay more for this two-toned premium cherry than for other sweet cherries. And, over the years, they’ve become increasingly popular. The 2018 crop was the largest ever for Rainiers, according to an annual review by the Northwest Cherry Growers, a Yakima-based organization that markets cherries for growers in Washington, Oregon, Idaho, Montana, and Utah. Packers moved 2.52 million boxes of Rainier cherries last year, breaking the previous record of 2.36 million in 2014.

Named for Mount Rainier and developed at WSU, Rainier cherries are a cross between two cultivars: the Bing, which originated in Oregon in 1875, and the Van, which originated in British Columbia in 1936. “I was just as surprised as anyone that ‘white’ ones showed up,” Harold Fogle told The Seattle Times in 2004. The late USDA breeder developed Rainier cherries at WSU’s research station in Prosser in 1952. Back then, Fogle told The Times, “we didn’t really understand the genetics of cherries.”

Fogle had been looking to create a new Bing variety to help extend cherry season. The richly red Bings and Vans he crossbred carried a recessive gene, and the result was P 1-680. It stood out, Fogle told The Times, “from the moment I first saw it ripen.”

Golden-hued Rainier cherries were first released in 1960. Despite their unusual good looks and natural sweetness, Whiting says, they were “initially sold out as a pollinizer. The Bing itself is sterile and needs a compatible pollinizer tree to fertilize its flowers.” Rainiers were largely planted to support Bing crops until the early 1980s, when growers really began to realize their potential on the fresh market. “Now,” Whiting says, “it is the premier cherry around the world.”

Sweet cherries are thought to have come from the region between the Black and Caspian seas, and cultivation is believed to have begun with the Greeks. Colonists brought sweet cherries to the New World, and they arrived in the Pacific Northwest in 1847 when Henderson Luelling traveled from Iowa to Oregon with nearly 1,000 trees and shrubs. His younger brother, Seth, later developed the Bing, named for his Chinese workers’ foreman, Ah Bing.

Today, Washington state is the top producer of sweet cherries in the country. According to the Washington State Department of Agriculture, sweet cherries are the state’s number six cash crop with a value of about a half billion dollars.

Growing cherries of any variety is a fickle business. Birds love them. And there’s that thin skin. A summer rainstorm can split it. Rainiers are super sensitive—not just on the tree but also during the process of picking and packing. “They’re not easy to grow,” Whiting says. “The number one issue is bruising, and when they’re damaged it shows up. With most cherries, the color of the skin can mask the bruising.” Rainiers, he says, need “to be handled with care and patience.”

Growers pay more for that special attention. “They typically have their best pickers handle their Rainiers,” Whiting says. “They pay them at a higher rate to go slow.” The idea is to encourage workers to exercise caution, select fruit for optimal color and size, and gently lay—not drop—the tender fruit into a bucket worn around the neck. In Prosser, at WSU’s Irrigated Agriculture Research and Extension Center, Whiting does research to support the entire sweet cherry industry. He works with growers to improve yields, production efficiencies, and labor-saving techniques as part of WSU’s Pacific Northwest Sweet Cherry Breeding Program.

WSU re-established the cherry program in 2004, after a hiatus of two dozen years, to develop superior new cultivars for the Pacific Northwest sweet cherry industry. One area of research is breeding resistance to diseases, particularly powdery mildew, which attacks both the foliage and fruit. “It’s primarily a Pacific Northwest problem,” says Per McCord, WSU’s new cherry breeder and associate professor of stone fruit breeding and genetics. “It won’t kill the tree, but it will certainly make the fruit unmarketable and that’s why it’s such a challenge. There’s also a risk of losing the ability to control it via chemicals, so that makes breeding an attractive option.”

Rainiers could still be improved. They, too, are susceptible to powdery mildew. And, like both of its parent varieties, Rainiers require a compatible pollinizer. “That’s one area you could improve upon for the grower: to produce a Rainier cherry that’s self-fertile and doesn’t require another cherry to pollinate it,” McCord says. “If we could develop a blush variety that was earlier or later than the Rainier, we could increase the market window for that class of cherry.”

Meantime, these blushing beauties—plump, juicy, and a good source of Vitamin C—are best enjoyed fresh, according to Cook’s Illustrated. Use raw Rainiers to top desserts or add a pop of color to a green salad. Chop them up for salsa. Muddle them into a cocktail. Eat them straight from the bowl. They’re simply too pretty to tuck into a pie. But, if you want to bake with them, consider WSU executive chef Jamie Callison’s Rainier Cherry Clafoutis. His take on the firm French custard—traditionally made with whole dark sour cherries from the Limousin region—is completed by orange zest and a splash of orange liqueur.

McCord personally likes fruit with a bit more acidity. But, no matter how Rainiers and other sweet cherries evolve, McCord says, they’re “always going to be a premium fruit. I don’t think we’re going to see bargain sweet cherries. It’d be like saying a bargain BMW.”

 

Web extra

Recipe: Rainier cherry clafoutis

 

On the web

WSU Tree Fruit

Northwest Cherry Growers