OUR MODERN ERA of superior plums really began with an indefatigable plant breeder by the name of Luther Burbank, who lived during the late 19th and early 20th centuries. From his home in Santa Rosa, California, and his 11-acre experimental farm in nearby Sebastopol, he introduced over 700 varieties of fruits, vegetables, and ornamental plants to the world, including the russet potato, the Shasta daisy, the thornless blackberry, and the Santa Rosa plum.

In 1885, Burbank started bringing in Japanese plums to crossbreed with American ones, in the hope of creating new delicious varieties. He made over 30,000 crosses of plums alone, and by the 1920s had released 113 new varieties of hybrid plums, many of which are still with us today. One of the sweetest, most exquisite of these Japanese cross breeds he named the Santa Rosa; it continues to be the gold standard for Japanese-type plums.

When I moved to Sonoma County, one of the first places I visited was Luther Burbank’s home and gardens in Santa Rosa. This was a fascinating place, still tenuously in touch with Burbank himself, although he died in 1926. Here were cacti he’d charmed into dropping their needles, the Cedar of Lebanon he planted in the first decade of the 20th century, his original hybrid Paradox walnut tree that grew cabinet-quality wood quickly, and the original Santa Rosa plum tree he’d introduced in 1907—at 78 years it was just a scraggly old stick, but still alive and hanging in there.

THE ORGANIC FACTOR

Most of our country’s fresh plums and 99 percent of prunes (dried plums) are grown in California. Conventional growers use agricultural chemicals to deal with a number of difficult pests and diseases, including plum curculios, brown rot, bacterial cankers, aphids, and scale. Organic growers have the same problems to deal with, but the healthier the tree and the more biodiverse the orchard, the less severe the problems tend to be. Still, organic remedies exist for all these problems. I find that organic plums, from trees cared for in an environmentally sensitive way, taste noticeably superior to most conventional types, with a richer, more concentrated flavor. Unsulphured organic prunes (important for people with certain allergies) are widely available at organic supermarkets and online, too.

NUTRITION

All types of plums have good stores of potassium and vitamin C and also contribute selenium, a cancer-fighting antioxidant.

TYPES

Plums most frequently encountered in our markets are hybrids of Japanese and European or American plum varieties. Lesser amounts of pure Japanese, American, and European plums are sold—but they are available.

The Japanese plum (Prunus salicina) thrives in California’s moderate climate but is problematic at best where late frosts are common. That’s because all Japanese plums flower very early—bursting into bloom in February and early March around the San Francisco Bay area. Most years that’s late enough to avoid hard frosts, but occasionally those blossoms do get pinched. These plums are juicier than American or European plums and typically larger.

Santa Rosa plums are the best known of the Japanese-type plums and have become the standard of quality for fresh plums across the nation, holding down about a third of the market. One taste of a perfectly ripe Santa Rosa and you’ll know why. It’s an aromatic, very sweet Japanese-type plum of exquisite flavor, with an evenly red skin, and juicy, yellowish flesh with red overtones. Variations of Santa Rosas have been selected for late blooming, and consequent late ripening, and today we have early to main crop Santa Rosas that appear in mid to late June, a midseason crop that ripens into early July, and a late season crop that matures in late July to mid-August. Many other Japanese-type plums have been introduced over the years, including Beauty, Friar, and Redheart.

The European plum (Prunus domestica) is probably a cultivated hybrid of the wild European blackthorn, or sloe (Prunus spinosa), and the cherry plum (Prunus cerasifera). This type ripens in late August or early September and includes Italian prune plums and varieties such as Coe’s Golden Drop and Stanley. The flesh is dense and sweet, greenish to yellow, usually freestone, and the skin varies from yellow to blue-black, usually with a dusty bluish bloom.  ....read more